Guidebook - Ispra
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Field Trip Guide Book - B12<br />
Volume n° 1 - from PR01 to B15<br />
32 nd INTERNATIONAL<br />
GEOLOGICAL CONGRESS<br />
GEOLOGICAL STRUCTURE<br />
OF THE ROMANIAN<br />
CARPATHIANS<br />
Leader: M. Sandulescu<br />
Associate Leader: R. Dimitrescu<br />
Florence - Italy<br />
August 20-28, 2004 Pre-Congress B12
The scientific content of this guide is under the total responsibility of the Authors<br />
Published by:<br />
APAT – Italian Agency for the Environmental Protection and Technical Services - Via Vitaliano<br />
Brancati, 48 - 00144 Roma - Italy<br />
Series Editors:<br />
Luca Guerrieri, Irene Rischia and Leonello Serva (APAT, Roma)<br />
English Desk-copy Editors:<br />
Paul Mazza (Università di Firenze), Jessica Ann Thonn (Università di Firenze), Nathalie Marléne<br />
Adams (Università di Firenze), Miriam Friedman (Università di Firenze), Kate Eadie (Freelance<br />
indipendent professional)<br />
Field Trip Committee:<br />
Leonello Serva (APAT, Roma), Alessandro Michetti (Università dell’Insubria, Como), Giulio Pavia<br />
(Università di Torino), Raffaele Pignone (Servizio Geologico Regione Emilia-Romagna, Bologna) and<br />
Riccardo Polino (CNR, Torino)<br />
Acknowledgments:<br />
The 32 nd IGC Organizing Committee is grateful to Roberto Pompili and Elisa Brustia (APAT, Roma)<br />
for their collaboration in editing.<br />
Graphic project:<br />
Full snc - Firenze<br />
Layout and press:<br />
Lito Terrazzi srl - Firenze
Volume n° 1 - from PR01 to B15<br />
32 nd INTERNATIONAL<br />
GEOLOGICAL CONGRESS<br />
GEOLOGICAL STRUCTURE OF THE<br />
ROMANIAN CARPATHIANS<br />
AUTHORS:<br />
M. Sandulescu (University of Bucharest - Rumania),<br />
R. Dimitrescu (Romanian Academy, Bucharest - Rumania)<br />
Florence - Italy<br />
August 20-28, 2004<br />
Pre-Congress<br />
B12
Introduction<br />
The fieldtrip “Geological Structure of the Romanian<br />
Carpathians” strives to cross the major tectonic units<br />
of this segment of the Tethyan Chains, with the<br />
purpose of presenting a general approach to the tectonic<br />
and paleogeographic (paleotectonic) problems.<br />
Knowledge of Carpathian geology allows us to understand<br />
the prolongation of the Alps toward the Balkans<br />
and the Dinarides. In order to accomplish the abovementioned<br />
tasks during the fieldtrip, a part of the<br />
significant geological cross sections in the East and<br />
South Carpathians as well as in the Apuseni Mts will<br />
be visited. Thus we will examine the tectonic units issued<br />
from the Tethyan Ocean - squeezed in the Main<br />
Tethyan Suture Zone or obducted on the continental<br />
margins – and their deformed continental margins.<br />
In the areas crossed by the fieldtrip geological maps<br />
and older fieldtrip guidebooks are available. It should<br />
be remembered that in respect to the geological maps<br />
or other guides, in the guidebook proposed here more<br />
or less important differences are possible, determined<br />
by the progress of our knowledge and/or a better understanding<br />
of the geological processes.<br />
Geological Map of Romania, scale 1: 200,000, sheets:<br />
Rădăuti, Topliţa, Piatra Neamţ, Odorhei, Brașov,<br />
Turda, Brad, Deva, Tg. Jiu, Baia de Aramă, Reșiţa.<br />
Geological Map of Romania, scale 1: 50,000, sheets:<br />
Vatra Dornei, Pojorâta, Câmpulung Moldovenesc,<br />
Dămuc, Voșlăbeni, Miercurea Ciuc, Brașov, Zărnești,<br />
Codlea, Zlatna, Câmpeni, Avram Iancu, Biharia, Brad,<br />
Deva, Lupeni, Schela, Tismana, Obârșia Cloșani,<br />
Orșova, Reșiţa, Bocșa.<br />
The Structure of the East Carpathians (Moldavia-<br />
Maramureș Area) by M. Săndulescu et al., 1981,<br />
Guide to Excursion B1.<br />
Structural Relations between Flysch and Molasse<br />
(The East Carpathians Model) by M.Săndulescu et<br />
al., 1981, Guide to Excursion A5.<br />
The Structure of the Apuseni Mountains by M.Bleahu<br />
et al., 1981, Guide to Excursion B3.<br />
Metamorphosed Paleozoic in the South Carpathians<br />
and Its Relations with the Pre-Paleozoic Basement by<br />
H.Kräutner et al., 1981, Guide to Excursion A1.<br />
The Structure of the South Carpathians (Mehedinţi-<br />
Banat Area) by S.Năstăseanu et al., 1981, Guide to<br />
Excursion B2.<br />
Excursion to South Carpathians, Apuseni Mountains<br />
and Transylvanian Basin. Description of stops by<br />
Berza et al., 1994 ALCAPA II.<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Leader: M. Sandulescu<br />
Associate Leader: R. Dimitrescu<br />
Geology of the South Carpathians in the Danube<br />
Gorges (Romanian Bank) by Pop et al., 1997.<br />
General Geological Setting<br />
General Structure and Evolution of the Romanian<br />
Carpathians<br />
(according to Săndulescu, 1980, 1984, 1994)<br />
The Carpathians are a segment of the Tethyan<br />
Chains; toward west they join the Alps and toward<br />
south and south-east the Balkans and the Rhodope.<br />
The Carpathian Foreland includes several platforms<br />
(Scythian, Moesian) or cratons (East European) as<br />
well as the Cimmerian North Dobrogea Orogen<br />
(Figure1). The Carpathian Folded Area is the result<br />
of several tectogenetic events of different ages: Cretaceous<br />
(generating the Inner Zones named Dacides)<br />
and Miocene (the Outer Zones named Moldavides).<br />
Upper Cretaceous and/or Paleogene post-tectogenetic<br />
covers develop above the Inner Zones. The Pannonian<br />
and the Transylvanian, Neogene molassic depressions<br />
overlie important parts of the Inner Zones and a part<br />
of their post-tectogenetic covers. A Neosarmatian-Eopleistocene<br />
molassic asymmetric foredeep develops<br />
in front of the Orogen, partly (inner limb) superposed<br />
on its external zones (Figure 1). The Folded Area can<br />
be divided into several major tectonic ensembles:<br />
The Main Tethyan Suture Zone (MTS) which<br />
groups together tectonic units constituted by Middle<br />
Triassic-Middle Jurassic ophiolitic complexes overlapped<br />
by sedimentary formations whose age (Middle<br />
and Upper Triassic, Jurassic or Upper Jurassic-Lower<br />
Cretaceous) is different from the age of the ophiolites<br />
they cover. The MTS which runs along the Vardar<br />
Zone (between the European and the Apulian continental<br />
margins) splits – from Beograd toward north<br />
or north-west - into two branches: the South Pannonian<br />
(separating the Apulian microplate from the<br />
Fore-Apulian one) and the Transylvanidian-Pienidian<br />
(situated between the European and the Fore-Apulian<br />
margins) (Figure2).<br />
The Fore-Apulian Microcontinent (FAM) is situated<br />
on the opposite side with respect to the European<br />
margin, considering the MTS a major geotectonic axis<br />
of symmetry of the Tethyan Chains. The FAM groups<br />
together the Austroalpine, the Central West Carpathians<br />
and the North Apusenide units (Figure 1), as well<br />
as the units covered by the Pannonian Depression<br />
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Figure 1 - Tectonic Sketch of Romania (acc. to<br />
Săndulescu, 1994). Carpathian Foreland: 1- East<br />
European Craton, 2 - Scythian (Sy) and Moesian (Mo)<br />
platforms, 3 - North Dobrogea Orogene. Carpathians: 4 -<br />
Inner Dacides (Northern Apusenides), 5 - Transylvanides,<br />
6 - Pienides (5 + 6 - Main Tethyan Suture), 7 - Median<br />
Dacides (Crist. - Mesoz. Zone, Getic and Supragetic), 8<br />
- Outer Dacides (Ceahlau- Severin), 9 - Marginal Dacides<br />
(Danubian), 10 - Moldavides, 11 - Post - tectogenetic<br />
covers, 12 - Neogene Molasse depressions and Foredeep,<br />
13 - Up. Cret.- Paleoc. magmatic arcs, 14 - Neogene<br />
magmatic arcs, 15 - thrust - sheets, 16 - faults.<br />
(Figure 2).<br />
The European Continental Margin (ECM) groups<br />
together the main part of the East Carpathians (the Pienides<br />
belong to the MTS) and the South Carpathians.<br />
There are two basic types of units: basement shearing<br />
nappes and cover nappes. The first type is built up of<br />
crystalline formations (metamorphics and sometimes<br />
acid and/or intermediate granitoids) and their normal<br />
sedimentary envelope (sedimented on the continental<br />
margin). This type of unit, which developed in the<br />
FAM too, constitute the Central East Carpathians<br />
(the Crystalline-Mesozoic Zone excepting the Transylvanian<br />
nappes which are obducted from the MTS<br />
- Figure 1,2), its correspondent in the South Carpathians<br />
(Getic-Supragetic ensemble) and the Danubian<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
(Figure 1). The cover type of nappes are well developed<br />
in the Flysch Zone of the East Carpathians and<br />
in the Subcarpathians. In the South Carpathians only<br />
the Severin Nappe (situated tectonically between the<br />
Getic Nappe and the Danubian) is of this type.<br />
Geotectonic History.<br />
End-Proterozoic (Panafrican) cratonisation is recognized<br />
in the whole Carpathian Foreland and in<br />
the Carpathian Orogen as relics. This huge cratonic<br />
area, preserved actually in the East European Craton,<br />
was split south and west of the former within the<br />
Paleozoic mobile areas. The folded basement of the<br />
Scythian Platform proceeds from one of these, while<br />
the Paleozoic metamorphic series of the Carpathians<br />
comes from another branch. Within these branches,<br />
remnants of Paleozoic oceanic crust-bearing domains<br />
Figure 2 - The major Tethyan sutures and continental<br />
areas in the Carpathian realm (post- tectonic covers is not<br />
shown) (acc. to Săndulescu, 1987). 1 a - Inner Dacides,<br />
1/2 - Bükk Unit and correlative units, 2 - Major Tethyan<br />
Suture (Vardar, South Pannonian, Transylvanides,<br />
Pienides etc), 3 - Măgura Group (belonging to the<br />
suture, 4 - Median Dacides (Central East - Carpathians,<br />
Getic & Supragetic nappes), 5 - Outer Dacides<br />
(Ceahlău - Severin), 6 - Marginal Dacides (Danubian),<br />
7 - Moldavides. Bc - Bucharest, Be - Beograd, Bd -<br />
Budapest, K - Krakow, W - Wien.<br />
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Figure 3 - Palinspastic sketches of the Carpathians and<br />
their Foreland during the Mesozoic and Paleogene. 1<br />
- Tethyan oceanic crust, 2 - Thinned and / or oceanic<br />
crust (Pindus), 3 - Thinned and oceanic (a) crust (Outer<br />
Dacides), 4 - North Dobrogea - South Crimea Cimmerian<br />
Aulacogene, 5 - Continental crust, 6 - deformed oceanic<br />
crust, 7 - Thinned crust of Moldavides. AA - Austroalpine,<br />
Aai - Lower Austroalpine, Aas - Upper Austroalpine, AM<br />
- Apuseni Mts., B - Bükk, BA - Balkanides, Bi - Bihor, Cc<br />
- Choc, Ch - Ceahlău, COC - Central East Carpathians,<br />
CWC - Central West Carpathians, D - Danubian, Dj -<br />
Djirula, EA - Eastern Alps, MM - Moesia, M - Măgura,<br />
ND - North Dobrogea, P - Pieniny Klippen, Pd - Pindus,<br />
Pn - Pontides, Rh - Rhodopes, SC - South Crimea, SCA<br />
- South Carpathians, Sge - Getic and Supragetic, Si<br />
- Silicicum, Sv - Severin, SP - Serbo - Pelagonian, Ta -<br />
Tatrides, WA - Western Alps.<br />
seem to be acceptable. A second large cratonisation<br />
occurs after the Early Carboniferous, including the<br />
Carpathians and parts of its Foreland.<br />
The earliest riftings – Early Triassic – occur along<br />
the future Tethyan Ocean and in the North Dobrogea-<br />
South Crimea Aulacogene. The first one precedes<br />
the opening of the oceanic Tethys, the second one<br />
represents a possible pull-apart structure connected<br />
to the right-lateral strike-slip movements along the<br />
Tornquist-Teisseyre Lineament. Tethyan oceanic<br />
spreading starts in the Middle Triassic (in accordance<br />
with the age of the oldest ophiolites which were<br />
obducted from the Transylvanidian suture) separating<br />
the Fore-Apulian Microcontinent from the European<br />
Continental Margin. The spreading processes<br />
continue during the Late Triassic, Early and Middle<br />
Jurassic, the Pienidian segment of the Tethys opening<br />
and spreading during this last period (Figure3). Rifting<br />
processes occur during the late Early Jurassic and<br />
the Middle Jurassic within the European Continental<br />
Margin (the Black Flysch-Ceahlău-Severin Rift). The<br />
opening of the Tethys and the distension of the mentioned<br />
rift, accompanied by the north-eastern motion<br />
of the Moesian Block, determine the compressive<br />
deformation of the North Dobrogea-South Crimea<br />
Aulacogene. At the Middle/Late Jurassic boundary<br />
the Tethyan Ocean reaches its maximum size, the<br />
youngest ophiolites proceeding from it being of pre-<br />
Kimmeridgian age.<br />
The earliest meaningful crustal shortening in<br />
the Carpathian Tethys was recorded in the latest<br />
Tithonian/earliest Neocomian. It consists of oceanic<br />
crust subduction below oceanic crust (Marianne type<br />
subduction), expressed in the calc-alkaline volcanism<br />
which occurs in some units of the Transylvanides
(South Apuseni). A largely developed tectogenetic<br />
event is the Meso-Cretaceous one. It involved the<br />
European Continental Margin generating the basement<br />
shearing nappes of the Central East Carpathians<br />
(Median Dacides) and a part of the oceanic Tethys<br />
expressed in obductions above the former (Transylvanidian<br />
Nappes). Meso-Cretaceous shortenings<br />
are also known in the Getic-Supragetic Domain, as<br />
well as in the Ceahlău-Severin Rift. The Intra-Turonian<br />
(Pre-Gosau) tectogenetic compressional events<br />
affected the Fore-Apulian Microcontinent (Inner<br />
Dacides), although mesocretaceous deformations are<br />
also recorded. The End-Cretaceous tectogeneses determined<br />
the final closing of the oceanic Tethys in the<br />
Transylvanidian sector and partially in the Pienidian<br />
one (Figure3). The European Continental Margin was<br />
affected by the End-Cretaceous deformations, too. At<br />
that time the South Carpathians recess-type bending<br />
was accomplished by the westward motion of the<br />
southern panel of the Moesian Platform, facilitated<br />
by the right-lateral slip of the Intra-Moesian Fault<br />
(Figs.1, 3). The motion of the Moesian Platform was<br />
accompanied by the underthrusting of the Danubian<br />
(Marginal Dacides) below the Getic and Severin nappes<br />
determining the consumption of the crust of the<br />
Severin sector of the rift, process which generated the<br />
Banatitic (calc-alkaline) Arc intruded in the overriding<br />
units, the Getic-Supragetic nappes respectively. A<br />
similar calc-alkaline (“Banatitic”) arc develops within<br />
the margin of the Fore-Apulian Microcontinent, generated<br />
by subduction of the oceanic Tethyan crust<br />
below the continental crust of the yet deformed Inner<br />
Dacides (Figure 6 ).<br />
Starting with the Early Paleogene, the mobile areas,<br />
receiving important turbiditic (flysch) sedimentation,<br />
remain the Pienidian (Pieniny + Măgura) and<br />
the Moldavidian domains (Figure 3) as well as some<br />
post-tectogenetic basins (e.g. Maramureș-Bârgău).<br />
The Pieniny-Magura Domain, with a partly consumed<br />
oceanic crust, ends southward on the North<br />
Transylvanian Fault, which separated it from the<br />
yet “sutured” Transylvanidian sector of the oceanic<br />
Tethys. The Moldavidian sedimentary Cretaceous<br />
and Paleogene-Lower Miocene basins develop above<br />
a thinned crust, which will be consumed during the<br />
Miocene together with the crust of the Ceahlău sector<br />
of the Ceahlău-Severin Rift, during the Miocene generating<br />
the East Carpathian Neogene Volcanic Arc.<br />
The south-west end of the Moldavidian troughs is<br />
connected to the Intra-Moesian Fault (Figure1). West<br />
of it the Paleogene formations, which generally show<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
changed lithofacies with respect to the Moldavides,<br />
fill the Getic Depression. This represents a (proto-)<br />
foredeep of the South Carpathians (where Tertiary<br />
shortenings are not recognized).<br />
Geological Structure of the East Carpathians<br />
The Romanian East Carpathians are the natural southward<br />
prolongation of the Ukrainian East Carpathians.<br />
Conventionally the boundary between the East and<br />
North Carpathians is situated along the Dniester, San<br />
and Uj valleys, but from the geological point of view<br />
there are only minor changes (if they exist). Roughly<br />
the boundary between the East and South Carpathians<br />
shows the same features, but the correlation is more<br />
difficult because of the development of post-tectogenetic<br />
covers and a complex system of Quaternary<br />
Depressions.<br />
The major geological ensembles of the East Carpathians<br />
are (innward-outward) (Figure 1) (Săndulescu,<br />
1984, 1994): 1) The Pienides, situated north of the<br />
Transylvanian Depression and the North Transylvanian<br />
Fault; 2) The Crystalline-Mesozoic Zone<br />
(Median Dacides and Transylvanian nappes) and its<br />
post-tectogenetic cover (above which the Pienides<br />
are overthrust); 3) The Flysch Zone, showing an internal<br />
and an external zone; 4) The Subcarpathians.<br />
The innermost units of the Flysch Zone are grouped<br />
in the External Dacides, while the Moldavides group<br />
together the other units of the Flysch Zone and the<br />
Subcarpathians. Inward with respect to the Crystalline-Mesozoic<br />
Zone and crossing the Pienides, a<br />
Neogene Volcanic Chain develops.<br />
The Pienides consist of cover nappes overthrusted<br />
above the Upper Cretaceous-Paleogene-Lowermost<br />
Miocene post-tectogenetic cover of the Crystalline-<br />
Mesozoic Zone, during the Burdigalian.<br />
The Crystalline-Mesozoic Zone is built up of basement<br />
shearing nappes, each of them showing large<br />
developed metamorphic formations covered by a<br />
Mesozoic or Permo-Mesozoic sedimentary envelope.<br />
The nappes, of Meso-Cretaceous age, cover each<br />
other. They are (up/down) the Bucovinian Nappe, the<br />
Subbucovinian Nappe and the Infrabucovinian nappes.<br />
The metamorphics consist of several superposed<br />
series (partly tectonically as a result of Paleozoic tectonic<br />
events) (Tab.1) (Kräutner, 1983, 1985; Balintoni,<br />
1985, 1997). The most important part of them are<br />
mesometamorphic and Precambrian. The youngest<br />
one (Tulgheș Series) is of Lower Paleozoic age and,<br />
perhaps, epimetamorphic. During the Middle Triassic<br />
a first paleogeographical differentiation took place: on<br />
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Table 1 - Correlation Sketch of the Metamorphic<br />
Formations of the Centre. East Carpathians<br />
the Bucovinian-Subbucovinian domain shallow-water<br />
(mainly dolomites) carbonatic rocks are deposited,<br />
while on the Infrabucovinian domain basinal, weakly<br />
bituminous, dolomites and limestones develop. The<br />
Upper Triassic formations are absent (stratigraphic<br />
gap). The discordant Lower Jurassic is of shallowwater<br />
environment (hard-ground type or paralic), the<br />
Middle Jurassic is generally detritic. During the Tithonian-Neocomian<br />
time a second paleogeographical<br />
differentiation is recorded: along the external part of<br />
the Bucovinian domain a flysch trough develops, its<br />
arenites being supplied by some elevated parts of the<br />
Subbucovinian domain, while on the central Bucovinian<br />
domain and the Infrabucovinian one, pelagic limy<br />
sedimentation took place. A meaningful formation<br />
developed in the top of the Bucovinian sedimentary<br />
succession is the Aptian-Albian Wildflysch which<br />
contains the sedimentary klippen (“olistoliths”) proceeding<br />
from the Transylvanian nappes which are<br />
tectonically superposed on the Wildflysch.<br />
The Transylvanian nappes proceed from the Main<br />
Tethyan Suture Zone (Figs.1, 2) obducted during<br />
the Meso-Cretaceous tectogeneses. There are three<br />
main nappes (Perșani, Olt and Hăghimaș) with different<br />
lithostratigraphic successions and ages of the<br />
ophiolitic complexes from the basal part of the nappes<br />
(excepting the Perșani one proceeding from the rifting<br />
zone which precedes the opening of the Tethyan<br />
Ocean). Transitional successions between these three<br />
basic units may be also recorded.<br />
The Flysch Zone groups together cover nappes built<br />
up essentially of sedimentary formations detached<br />
from their primary basement and overthrusted eastward<br />
above the underthrust Foreland (Figure 4, 5).<br />
The innermost nappes (Black Flysch, Ceahlău,Baraolt<br />
etc.) (Figure 1) contain only Tithonian-Cretaceous<br />
formations, the Paleogene ones building up their posttectogenetic<br />
cover. The other units (the Moldavides)<br />
(Convolute Flysch, Macla, Audia, Tarcău, Marginal<br />
Folds) comprise Cretaceous, Paleogene and Miocene<br />
(Lower and Middle) sedimentary formations. The<br />
Subcarpathian Nappe (Figs. 1, 4, 5) is the outermost<br />
overthrust unit of the East Carpathians. It consists<br />
mostly of Miocene formations to which – in the core<br />
of some anticlines - Oligocene and exceptionally<br />
Upper Eocene ones are associated. The tectogenetic<br />
events which generated the actual structural features<br />
of the Flysch Zone and the Subcarpathians are:<br />
Meso-Cretaceous (overthrusting of the Black Flysch<br />
and Baraolt nappes and folding of the Ceahlău one),<br />
End-Cretaceous (overthrusting of the Ceahlau Nappe;<br />
slight folding of the Convolute Flysch Nappe), Intra-<br />
Burdigalian (overthrusting of the Convolute Flysch,<br />
Macla and Audia nappes), Intra-Badenian (overthrusting<br />
of the Tarcău Nappe and of the Marginal<br />
Folds Nappe) Intra-Sarmatian (overthrust of the Subcarpathian<br />
Nappe, the last important underthrusting of<br />
the Foreland).<br />
The Foredeep is an asymmetric molassic depression<br />
situated discordantly above the Foreland elements and<br />
the external deformed part of the chain (Figure 1, 4).<br />
In the Carpathian Bending Area the inner limb of the<br />
Foredeep is folded. The deformations took place during<br />
the Lower Pleistocene tectonic event known as the<br />
Wallachian “Phase” .<br />
Geological Structure of the South<br />
Apuseni Mountains<br />
The Southern Apusenides correspond on general lines<br />
to the prolongation of the Major Tethian Suture Zone<br />
which in the Balkan Peninsula is also known as the<br />
Axios -Vardar Zone. Around Belgrade, a branch of
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Figure 4 - General cross - section through the Romanian<br />
Carpathians (acc. to Săndulescu, 1984). Inner Dacides<br />
(1+ 2) : 1 - Codru - Arieșeni nappe system, 2 - Bihor<br />
Unit; Main Tethyan Suture: 3 - Transylvanides:<br />
Median Dacides (4 - 6) : 4 - Bucovinian Nappe, 5<br />
- Subbucovinian Nappe, 6 - Infrabucovinian nappes; 7-<br />
Remnants of the primary basements of the Flysch Zone in<br />
the Benioff paleoplane; Outer Dacides (8 + 9) : 8 - Black<br />
Flysch Nappe, 9 - Ceahlău Nappe; Moldavides (10 - 15)<br />
: 10 - Convolute Flysch, 11 - Macla Nappe, 12 - Audia<br />
Nappe, 13 - Tarcău Nappe, 14 - Marginal Folds Nappe,<br />
15 - Subcarpathians Nappe; Foredeep : 16- Focșani<br />
Depression; Underthrusted elements (17 + 18) : 17<br />
- Crystalline basement, 18- Sedimentary formations (Pz<br />
- Paleozoic, Mz - Mesozoic, Pg - Paleogene).<br />
the latter curving to the NE joins under the mainly<br />
Tertiary and Quaternary cover (Vojvodina-Banat) the<br />
complicated Southern Apuseni orogenic system emplaced<br />
mainly on oceanic crust; another branch, also<br />
concealed by younger formations, runs WNW along<br />
the Sava river (South Pannonian Suture - Săndulescu,<br />
1980, 1984). North and South of the Southern Apusenides<br />
suture zone, units with continental basement<br />
represent its margins, called respectively Internal,<br />
Median Dacides.<br />
The different units of the Southern Apusenides,<br />
mainly obduction nappes, consist of sedimentary Upper<br />
Jurassic and Cretaceous formations, at the base of<br />
which magmatic complexes of ophiolitic or island arc<br />
character were conserved. The age of the ophiolites<br />
is Middle Jurassic, whereas the calc-alkaline islandarc<br />
series belongs to the Upper Jurassic (Berriasian,<br />
at most).<br />
From north to south, the tectonic units which will be<br />
crossed during the excursion are: Bucium Unit, Feneș<br />
Nappe, Techerău Nappe, Căbești Nappe and Bejan<br />
Nappe. We shall describe them according to Bordea,<br />
1992 and Bleahu et al., 1981.<br />
The Bucium Unit overlies a crystalline basement<br />
characteristic of the Northern Apuseni (Internal<br />
Dacides). The sedimentary sequence starts with the<br />
Ciuruleasa Formation consisting of black argillaceous<br />
shales with sandstone lenses in which an Early Cretaceous<br />
flora was found. A sandy calcareous-shaly<br />
flysch-like formation called the Valea Povernei Formation<br />
follows, of Upper Hauterivian-Lower Aptian<br />
age, established according to paleophytological data<br />
(Antonescu, 1973). The most characteristic term of<br />
this formation is a quartzitic sandstone with calcareous<br />
matrix and calcitic veinlets, interbedded with dark<br />
argillaceous shales. Graded bedding and parallel or<br />
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Figure 5 - Synthetic cross - section through the East<br />
Carpathians (in central Moldavia) (acc. to Săndulescu,<br />
Stănică and Visarion in Săndulescu , 1994). B -<br />
Bucovinian Nappe, SB - Subbucovinian Nappe, IB<br />
- Infrabucovinian Nappe, FN - Black Flysch Nappe, CH<br />
- Ceahlău Nappe, FC - Convolute Flysch Nappe, M -<br />
Macla Nappe, A - Audia Nappe, TC - Tarcău Nappe, MA<br />
- Marginal Folds Nappe, SC - Subcarpathians Nappe,<br />
Cr - crystalline formations, Pz - 3 - Upper Paleozoic, Mz<br />
- Mesozoic, N - Neogene, Th - Tithonian, k 1 - Lower<br />
Cretaceous, k 2 - Upper Cretaceous, Pg 1 - Paleocene, Pg<br />
2 - Eocene, o 1 - Oligocene, m 1 - Lower Miocene, m 2<br />
- Middle Miocene.<br />
cross lamination can sometimes be observed.<br />
Next, a shaly-calcareous flysch formation consisting<br />
of calcareous sandstones, calcarenites and calcirudites<br />
with intercalations of greenish-grey shales follows<br />
conformably. In the graded calcarenites elements of<br />
mafic rocks and of Neojurassic limestones can be<br />
observed. The Aptian age of this formation was demonstrated<br />
by Brachiopods (Belbeckella gibbsiana),<br />
Orbitolinids and a palynological association.<br />
The sequence continues with the Soharu Formation,<br />
which could be characterized as a grey argillaceous<br />
flysch with Wildflysch episodes. It consists of siltstones<br />
and weakly calcareous sandstones, dark clays,<br />
calcirudites and conglomerates with pebbles of mafic<br />
rocks and limestones.<br />
Micropaleontological evidence as well as Ammonites<br />
limit the age as Upper Aptian-Lower Albian.<br />
A grey Lower Albian Wildflysch Formation with<br />
olistoliths of Upper Jurassic massive limestones and<br />
mafic rocks represents a lateral facies variation of<br />
the Soharu Formation. Besides the chaotic blocks of<br />
calcirudites, calcarenites, polymictic conglomerates,<br />
basic tuffs or jaspers, a paratypic flyschoid facies<br />
also occurs.<br />
The Upper Albian is represented by the Pârâul Izvorului<br />
Formation. It consists of a grey flysch with evident<br />
graded bedding and convolute structure, the main<br />
rock types being micaceous sandstones and marls.<br />
The constraining macro-and micropaleontological<br />
data were found in the same formation occurring in<br />
another structural unit (the Curechiu Nappe).<br />
At its upper part, the Pârâul Izvorului Formation passes<br />
into the ortho-quartzitic Negrileasa Conglomerates<br />
(Cenomanian).<br />
The Senonian of the Bucium Unit overlies transgressively<br />
the previously described formations as well<br />
as the crystalline schists of the Northern Apuseni<br />
Mountains. It starts with a Upper Santonian Gosau<br />
Formation (rudist-bearing limestones) followed by
grey marls with Inoceramus balticus and a grittyshaly<br />
micaceous flysch.<br />
The Feneș Nappe is overthrown northwards onto the<br />
Bucium Unit and has an ophiolitic basement. It begins<br />
with the Feneș Formation, the most significant within<br />
the Southern Apusenides. It could be defined as a volcano-sedimentary<br />
calcareous olistostrome with flysch<br />
sequences, and starts with a thick turbiditic sequence<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Figure 6 - Structural cross - section through the Apuseni<br />
Mts. and the South Carpathians (acc. to Săndulescu,<br />
Stănică and Visarion in Săndulescu ,1994). 1 - Bihor Unit<br />
(BH) (a - sedimentary formations), 2 - Codru - Arieșeni<br />
nappes system (CA), 3 - Biharia nappes system (B) (a<br />
- Gosau Formation), 4 - Transylvanides (M) (Southern<br />
Apusenides) (Main Tethyan Suture), 5 - Getic (G) and<br />
Supragetic (SG) nappes (a - sedimentary formations), 6<br />
- Severin Nappe (SV), 7 - Danubian (DA), 8 - Senonian<br />
- Paleocene calc - alkaline magmatites (Banatites), 9 -<br />
Moho Discontinuity.<br />
of quartz sandstones and grey clays which towards the<br />
top grades into slumped clays with interbedded tuffs<br />
and spilitic lavas as well as with either massive bioconstructed<br />
or thin bedded micritic limestones. In the<br />
massive limestones, Pachyodonts were found providing<br />
proofs of their Barremian-Lower Aptian age.<br />
The Feneș Formation grades up into the turbiditic<br />
Valea Dosului Formation, consisting of calcareous<br />
polymictic conglomerates, alternating with sandstones,<br />
green clays and mafic pyroclastites. In intercalated<br />
calcarenites Orbitolinids were found, indicating<br />
an Aptian age.<br />
The Meteș Formation, overlying unconformably the<br />
two above-mentioned sequences, has a typical Wildflysch<br />
character. It includes two members: a lower<br />
one characterized by an olistostrome-like marly-silty<br />
facies with some interbedded turbiditic and coarse<br />
layered sandstones; an upper member which consists<br />
of breccias with silty-marly green, grey or reddish<br />
matrix and exolistoliths of ophiolitic rocks, Upper<br />
Jurassic massive limestones or granodiorites.<br />
The Upper Aptian-Middle Albian age of the Meteș<br />
Formation was established according to macropaleontological<br />
and palynological studies.<br />
Next follows the Valea lui Paul Formation, consisting<br />
of grey, loose sandstones which pass into sands.<br />
Micropaleontological and palynological studies have<br />
provided evidence of a Upper Albian-Cenomanian<br />
age.<br />
The Senonian of the Feneș Unit is represented by<br />
medium or fine-grained sandstones and polymictic<br />
conglomerates. A megabreccia Wildflysch Formation<br />
follows, interpreted by some authors as an independent<br />
unit (Valea Mică-Galda Nappe).<br />
The Techerău Nappe is developed in a widespread<br />
area in the western and the central part of the South<br />
Apusenides. It is the unit which shows a major part<br />
of the Tethian oceanic crust. Its basement consists of<br />
ophiolitic rocks as well as of an island arc calcalkaline<br />
series, which interfingers with Callovian radiolarites.<br />
The sedimentary sequence starts with these jaspers<br />
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Figure 7 - Structural sketch-map of the Apuseni Mountains. .... Neogene molasse cover; vvvv Neogene calc-alkaline<br />
magmatites; +++ Upper Cretaceous calc-alkaline magmatites; Sn, post-tectogenetic cover of the North Apusenides.<br />
Northern Apusenides: Biharia Nappes System – BA, Baia de Arieș Nappe; ML, Muncel-Lupșa Nappe; B, Biharia<br />
Nappe; H P, Highiș (H) and Poiana (P) Nappes; Codru Nappes System: Co, Colești Nappe; Va, Vașcău Nappe; M<br />
A, Moma (M) and Arieșeni (A) Nappes; Vt, Vetre Nappe; D Ba, Dieva (D) and Bătrânescu (Ba) Nappes; S F, Șasa<br />
(S) and Ferice (F) Nappes; U, Următ Nappe; Fi G, Finiș (Fi) and Gârda (G) Nappes; Vl, Vălani Nappe; UB, Bihor<br />
Unit. Southern Apusenides: Ri, Rimetea Nappe; Be, Bedeleu Nappe. Bedeleu Nappes System: Fu, Fundoaia Nappe; H,<br />
Hospea Nappe; Bj, Bejani Unit; Bo, Bozeș Nappe; V Ar, Vulcan (V) and Ardeu (Ar) Nappes; Cb, Căbești Nappe; VG,<br />
Valea Mică-Galda Nappe; T, Techerău Nappe; C, Curechiu Nappe; FB, Feneș-Blăjani Nappe; Cr Fr, Criș (Cr) and<br />
Frasin (Fr) Nappes; Gr, Groși Nappe; Bu, Bucium Unit. Median Dacides: DM, Supragetic Nappes<br />
followed by Oxfordian micritic limestones and massive<br />
limestones of Kimmeridgian-Tithonian age. Barremian<br />
-Aptian (?) marly or sandy limestones with<br />
Orbitolinids overlie the Upper Jurassic limestones as<br />
well as the eruptive rocks directly.<br />
Wildflysch sequences consisting of dark clays containing<br />
olistoliths of Upper Jurassic and Urgonian<br />
limestones and mafic rocks directly overlie the basement<br />
in several places. In places, interbedded sandstones<br />
and marly sequences, ascribed to the Albian,<br />
are also present.<br />
The following two units are bordered by EW trending<br />
vertical dislocations probably with a horizontal<br />
displacement, parallel to the South Transylvanian<br />
Fault. Consequently, their overthrusting character is<br />
impossible to evaluate.<br />
The Căbești Unit begins with the Cpbești Formation,<br />
an olistostrome with quartz sandstone-shaly flysch -<br />
like sequences. It is ascribed to the Barremian, by<br />
comparison with the Valea Povernei Formation. It<br />
is overlain by the Fornpdia Formation, consisting of<br />
quartzose conglomerates which laterally pass into<br />
calcareous sandstones, ascribed to the Vraconian<br />
(uppermost Albian) due to the Ammonites found. The<br />
calclithitic sequence which follows, as well as reddish<br />
marls, are considered to belong to the Cenomanian,<br />
also due to Ammonite faunas.<br />
The Bejan Unit is the southernmost one of the<br />
South Apusenides. The Bejan Formation consists of<br />
a Wildflysch with exolistoliths of basalts, Triassic and<br />
Upper Jurassic-Neocomian limestones embedded in<br />
black argillaceous clays with intercalations of basaltic
flows and pyroclastics. Its age was ascribed to the<br />
Barremian.<br />
The Deva Formation which follows after an evident<br />
unconformity is represented by poorly sorted, loose,<br />
thick bedded sandstones interbedded with silty marls.<br />
According to palynological data, its age may be assigned<br />
to the Turonian and Senonian.<br />
The Bozeș Nappe represents the uppermost unit in<br />
the south-eastern part of the Southern Apuseni. The<br />
Bozeș Formation represents its main lithostratigraphic<br />
term. It is a typical flysch formation in which the<br />
following rock types can be recognized: sandstones,<br />
silty marls and microconglomerates. Graded bedding,<br />
sole markings and bioglyphs are frequent. Towards<br />
the top, the flysch sequence is replaced by a molassic<br />
one, with conglomerate levels. The top itself consists<br />
of continental deposits. The age of the formation is<br />
ascribed to the Senonian, reaching the Maastrichtian,<br />
established on the basis of faunal remains and microfaunal<br />
studies.<br />
Mesozoic eruptive rocks.<br />
At the beginning of the eighties, Savu (1981) for<br />
the first time stated the clear distinction between the<br />
ophiolitic complex of the South Apusenides, consisting<br />
of a tholeiitic series, and an island arc volcanism<br />
forming a calc-alkaline series, emplaced in the same<br />
Carpathian unit.<br />
The most recent data concerning both magmatic complexes<br />
are due to Saccani et al. (2001), Bortolotti et al.<br />
(2002) and Nicolae, Saccani (2003). We shall describe<br />
them according to the latter.<br />
The ophiolitic sequence is characterized by: 1) an intrusive<br />
section represented mainly by small gabbroic<br />
bodies as well as scarce ultramafic cumulates; 2) a<br />
basaltic sheeted dike complex; 3) a volcanic sequence<br />
including basalts and rare pillow breccias; 4) very rare<br />
Callovian radiolarian chert.<br />
Basaltic rocks display MORB patterns and a high-Ti<br />
magmatic affinity; all the geochemical features suggest<br />
that the ophiolites were generated in a mid-ocean<br />
ridge setting and that they can be correlated with the<br />
ophiolites of the Vardar-Axios zone. K-Ar ages of<br />
microgabbros, dolerites and basalts from the Mureș<br />
Valley (Techerău Nappe) fall between 138.9 ± 6.0<br />
and 167.8 ± 5.0 M. a. (Middle to Upper Jurassic)<br />
(Nicolae et al., 1992).<br />
The overlying calc-alkaline rocks are represented<br />
by massive lava flows including basalts, andesites,<br />
dacites and rhyolites, as well as by some granitoid<br />
complexes intruded into the ophiolitic sequences;<br />
they show locally high-K calc-alkaline affinity. This<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
series represents a magmatic island-arc setting developed<br />
over the previously formed oceanic lithosphere.<br />
Relations with sedimentary formations constrain the<br />
age of the calc-alkaline series to the Upper Jurassic.<br />
No genetic relationship with the underlying ophiolitic<br />
rocks exists. A younger alkaline series consists of limburgites,<br />
trachyandesites (oligophyres) and trachytes<br />
(orthophyres) intercalated in the Lower Cretaceous<br />
Feneș beds.<br />
Microtectonics and metamorphism<br />
of the Feneș beds.<br />
Two folding phases developed during the time-span<br />
from Early Aptian to Late Maastrichtian. The D1<br />
phase produced west-northwest-verging isoclinal<br />
to very tight folds, associated to a slaty cleavage.<br />
Illite and chlorite were formed, metamorphic conditions<br />
being close to the diagenetic zone/anchizone<br />
boundary. The subsequent D2 phase produced northnorthwest-<br />
verging, parallel folds. The burial of the<br />
formation took place at a depth of 8-10 km (Ellero<br />
et al., 2002).<br />
Main tectonic features The geotectonic evolution of<br />
the Southern Apusenides was typically polyphasic.<br />
The Mesocretaceous tectogenesis involved two<br />
moments:1) the first one, in the uppermost Aptian,<br />
marked some unconformities in the Bucium, Feneș<br />
and Căbești Units; 2) the second, an intra-Late Albian<br />
one, was much more important and caused thrusting<br />
between some units. The Wildflysch character of some<br />
Albian formations pleads also for important compressive<br />
movements; 3) The pre-Gosau tectogenesis does<br />
not display evident structures. It is the Laramian tectogenesis<br />
that accomplished the structural framework<br />
of the Southern Apusenides. The overall transport<br />
direction of the nappes is a north- western one.<br />
Concerning the Neogene tectonics, it is noteworthy<br />
that characteristic NW-SE structures can be considered<br />
also as tectono-magmatic alignments.<br />
Geological Structure of the North<br />
Apuseni Mountains<br />
The Northern Apusenides (Internal Dacides) group<br />
together units issued from the deformation of a continental<br />
crust. These units consist of metamorphic and<br />
granitic basements of Precambrian or Paleozoic age<br />
and of sedimentary Upper Paleozoic and Mesozoic<br />
formations.<br />
Bihor Unit. It has to be underlined from the beginning<br />
that, although this fact is not compulsory, every<br />
Alpine tectonic unit having a crystalline “sole” is<br />
characterised by specific features of this metamorphic<br />
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basement.<br />
For the lowermost Bihor Unit, this basement consists<br />
of the medium-grade Somes Series (micaschists,<br />
amphibolites, leptynites) and the retrogressive Arada<br />
Series (chlorite-sericite-albite schists, metarhyolites),<br />
both intruded by the Muntele Mare granitic massif.<br />
The ages of the metamorphism and of the intrusion<br />
are Paleozoic.<br />
The sedimentary sequence of the Bihor Unit includes,<br />
(besides very scarce Permian) Triassic, Jurassic and<br />
pre-Senonian Cretaceous formations. The following<br />
specific lithostratigraphic features must be underlined:<br />
-development of a carbonatic platform series from the<br />
Upper Werfenian to the base of the Carnian;<br />
-absence of the major part of the Upper Triassic;<br />
-Gresten paralic facies of the Lower Jurassic;<br />
-marine sequence of the Middle Jurassic and of the<br />
base of the Upper Jurassic;<br />
-development of a carbonatic platform in the Kimmeridgian<br />
and the Tithonic;<br />
-lag of sedimentation at the base of the Cretaceous,<br />
marked by bauxites;<br />
-calcareous neritic lithofacies of the Barremian and<br />
Aptian, passing into a marly sedimentation which<br />
continues in the Turonian.<br />
The Bihor Unit corresponds to the Villàny Unit in<br />
southern Hungary and to the Tatride units in the<br />
Slovakian Carpathians, and is probably overthrust<br />
northwards onto the Tethysian Suture.<br />
Codru Nappes System. A number of nappes are overthrust<br />
from the SE onto the Bihor Unit; they correspond<br />
to the South Hungarian Bekes Realm.<br />
The first major unit, the Finiș-Gârda Nappe, has<br />
a metamorphic basement consisting of the Codru<br />
Granitoids and Migmatites, the oldest basic intrusions<br />
being pre-Hercynian (400 m. a.) according to<br />
Dallmeyer et al. (1994). As specific lithostratigraphic<br />
features, the following are to be mentioned:<br />
-large development of the Permian, with felsic ignimbritic<br />
volcanism;<br />
-complete development of the Triassic sequence, with<br />
Carpathian Keuper and Kössen facies in the Late and<br />
latest Triassic;<br />
-marine, marly-calcareous facies of the Lower<br />
Jurassic;<br />
-development of a flysch-type sequence in the Tithonian-Neocomian.<br />
The Următ Nappe is developed similarly to the Finiș<br />
Nappe, with lithofacial variations at the level of the<br />
Jurassic, which is of wildflysch type.<br />
The Dieva-Bătrânescu Nappe is characterized by:<br />
- a complex magmatism in the Permian, with mafic<br />
rocks intercalated between two rhyolitic sequences;<br />
- development of Reifling and Dachstein facies (until<br />
the Upper Norian);<br />
- a lag at the level of the Jurassic.<br />
The Moma-Arieșeni Nappe overlies all the other<br />
units including the Bihor Unit. The oldest formations<br />
of the former consists of the Lower Carboniferous<br />
Arieșeni Series (greenschists intruded by doleritic<br />
veins). The Upper Carboniferous and Permian molassic<br />
formations of reddish colour are well developped,<br />
including acidic eruptive products. The Middle and<br />
Upper Triassic formations, in calcareous facies, end<br />
with the Rhaetian.<br />
The highest nappes of the Codru System display Triassic<br />
sequences in Hallstatt and Dachstein facies.<br />
Biharia Nappes System. This group of nappes<br />
consists essentially of metamorphic formations of<br />
pre-Carboniferous age (Biharia Series: orthoamphibolites,<br />
chlorite-schists with albite porphyroblasts;<br />
Muncel Series: sericite schists, mylonitic granites,<br />
metarhyolites) overlain by the metaconglomeratic<br />
Upper Carboniferous Păiușeni Series.<br />
Post-tectogenetic cover. The nappes building up the<br />
Internal Dacides (Northern Apusenides), characterized<br />
by a Turonian principal tectogenesis (similarly to<br />
the Slovak Central Carpathians or to the Eastern Alps)<br />
are post-erosionally overlain by the Senonian Gosau<br />
Formation. The post-tectonic subduction magmatism<br />
is represented by banatites.<br />
Banatitic Late Cretaceous magmatism. In the<br />
Apuseni Mountains, an outstanding example of<br />
Late Cretaceous magmatism is the volcano-plutonic<br />
Vlădeasa Massif; a volcano-sedimentary formation is<br />
overlain by andesites, dacites and ignimbritic rhyolites,<br />
all crossed by quartz-dioritic and monzogranitic<br />
minor intrusions.<br />
Southwards, a granodioritic-granitic batholith crops<br />
out only on restricted areas and is also associated to<br />
andesitic and rhyolitic minor intrusions.<br />
Neogene magmatism. Neogene magmatic rocks in<br />
the Apuseni Mountains range in age from 14.8 to<br />
7.4 M. a., their calc-alkaline composition varying<br />
from basalt-andesites to dacites, andesites prevailing;<br />
many plot at the edge of the adakite field (Roșu,<br />
2001). They crop out along three main WNW - ESE<br />
to NW - SE trending lineaments (Brad-Săcărâmb,<br />
Stănija-Zlatna, Roșia Montană-Bucium), plus the<br />
Baia de Arieș zone.
Geological Structure of the South Carpathians<br />
As results from the general introduction, the South<br />
Carpathians, which extend from the Prahova Valley<br />
in the east to the Timok Valley in the south, consist<br />
of the following main Alpine structural elements:<br />
Lower Danubian Units, Upper Danubian Units, Severin<br />
Nappe, Getic Units, Supragetic Units. Important<br />
pre-Alpine tectonic units (nappes) are involved and<br />
preserved in these Alpine nappes. The Danubian on<br />
the one hand, the Getic and Supragetic Units on the<br />
other hand, represent two sialic microplates, while the<br />
Severin Nappe, lacking a metamorphic basement, is<br />
related to a basin with oceanic crust. With the exception<br />
of the latter, all the main Alpine units consist of<br />
a metamorphic basement including Precambrian and<br />
Paleozoic rocks and of a sedimentary cover beginning<br />
with a Variscan molasse and including Mesozoic formations<br />
up to the Senonian.<br />
South of the Danube, in Serbia and Bulgaria, the Danubian<br />
Realm corresponds to the Stara Planina, Miroc´<br />
and West Porec´ Units (Krstic´, Karamata, 1992).<br />
Lower Danubian Units The Lower Danubian units<br />
are represented by several pre-Alpine nappes with<br />
a common Upper Paleozoic-Mesozoic post-nappe<br />
cover; only in the south-eastern part of the area an<br />
important Alpine overthrust was recognized (Schela).<br />
The main pre-Alpine nappe (Retezat-Parâng Unit),<br />
consisting of a distinct sequence of polymetamorphic<br />
rocks (Drăgșan Group) intruded by granitoid<br />
bodies and covered by Lower Paleozoic low-grade<br />
formations, is overthrust onto metadetrital sequences<br />
of polymetamorphic rocks (Lainici-Păiuș Group),<br />
associated granites and low-grade Lower Paleozoic<br />
formations (Vâlcan-Pilugu Unit).<br />
Metamorphic basement. The Drăgșan G r o u p is<br />
exposed in the Retezat Mountains in the north and in<br />
the Mehedinţi-Vâlcan-Parâng Mountains in the south.<br />
Its main part is represented by an Amphibolite Formation,<br />
in which the dominant banded amphibolites are<br />
interlayered with biotite augen-gneisses, leptynites,<br />
mica gneisses and scarce serpentinites, crystalline<br />
limestones or kyanite-staurolite gneisses. Retrogressive<br />
events have caused alterations of amphibolites to<br />
greenschists over large areas. The volcano-sedimentary<br />
origin of the amphibolites from mafic igneous<br />
rocks and tuffs is evidenced by rock associations and<br />
chemical data.<br />
The Drăgșan rocks are intruded by the Retezat, Parâng<br />
and Culmea Cernei plutons, dominantly granodiorite<br />
bodies with biotite-hornblende diorites or biotite ±<br />
muscovite granites occurring in restricted areas.<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Zircon U-Pb data on an intercalated augengneiss have<br />
given an age of 777 ± M.a. for the emplacement of<br />
the protolith of the gneiss, while Nd model ages for<br />
the amphibolites range from 717 M.a. to 817 M.a.<br />
(Liégeois et al., 1996). Major and trace elements from<br />
the Drăgșan amphibolites consistently display an island<br />
arc signature. K-Ar model ages of the Drăgșan<br />
rocks or the associated granitoids range between 325<br />
and 97 M.a. (Grünenfelder et al., 1983), showing later<br />
reworking.<br />
The Lainici-Păiuș Group is exposed in the same two<br />
areas mentioned above (Retezat and Mehedinţi-Vâlcan-Parâng<br />
Mountains). The main features of this<br />
group are the sedimentary origin and the invasion<br />
of granitoids as a number of large plutons, countless<br />
small bodies and various migmatites.<br />
Two formations were recognized: a lower Carbonate-<br />
Graphitic Formation, consisting of crystalline<br />
limestones and dolomites, sillimanite-andalusite-<br />
cordierite-graphite mica gneisses, amphibolites and<br />
calc-silicate gneisses, and an upper Quartzitic and<br />
Biotite Gneiss Formation.<br />
The two main types of plutons intruded into the<br />
Lainici-Păiuș Group are the Șușiţa type and the<br />
Tismana type. The former is made up of medium-K<br />
calc-alkaline granodiorites and tonalites; the latter<br />
(Tismana and Novaci) belong to the shoshonitic<br />
series, displaying a complete range of compositions<br />
from ultramafic to felsic rocks. Widespread minglingmixing<br />
relationships give rise to a variety of facies. A<br />
liquid line of descent from the diorites to the granites<br />
was reconstructed. The intermediate and felsic rocks<br />
are commonly porphyritic (Duchesne et al., 1998).<br />
The ages of the various syn-to late-kinematic granitoid<br />
intrusives in the Lainici-Păiuș basement are in<br />
the 588 - 567 M.a. range (U-Pb zircon ages). The<br />
regional LP- HT metamorphism is probably not much<br />
older (Liégeois et al., 1996).<br />
Lower and Middle Paleozoic very low-grade formations.<br />
Although the presence of the Cambrian in the<br />
Lainici-Păiuș Group was advocated, the evidence is<br />
not convincing. The oldest Paleozoic sequence, the<br />
Upper Ordovician age of which was proved by paleontological<br />
evidence (Corals, Crinoids, Brachiopods<br />
as well as Acritarchs and Chitinozoans) is the Valea<br />
Izvorului Formation (quartzites, metaconglomerates<br />
and slates); notwithstanding its scarce development,<br />
it serves to constrain the age of the high-to mediumgrade<br />
metamorphic formations underlying it.<br />
A younger sequence is the Valea de Brazi Formation<br />
(metaconglomerates, sandstones, slates) attributed to<br />
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the Devonian.<br />
Upper Paleozoic and Mesozoic. The formations<br />
overlying the Variscan and pre-Variscan basement<br />
are the following: Permian red-beds; Lower Jurassic<br />
Gresten facies deposits (conglomerates, sandstones);<br />
Middle Jurassic sandstones with carbonatic matrix;<br />
Upper Jurassic-Lower Cretaceous massive limestones;<br />
Middle Cretaceous shales (Nadanova beds);<br />
Upper Cretaceous turbidites, reaching into the Senonian.<br />
A special mention has to be made of the northern part<br />
of the Lower Danubian Mesozoic displaying very<br />
low metamorphism: the Liassic Schela Formation<br />
(metaconglomerates and phyllites with chloritoid and<br />
pyrophyllite); the Upper Cretaceous volcaniclastic<br />
sandstones with prehnite and pumpellyite.<br />
Upper Danubian Nappes<br />
Metamorphic basement.<br />
The Upper Danubian Nappes are exposed in the<br />
northern and western parts of the Danubian Window.<br />
The Zeicani Group represents the polymetamorphic<br />
basement of several nappes and consists of a prevailing<br />
amphibolitic sequence, with associated leptynites<br />
and mica gneisses (± kyanite, staurolite) generally affected<br />
so strongly by retrogression that they look like<br />
greenschists or sericite schists. Berza and Seghedi<br />
(1983) compare this group with the Drăgșan Group of<br />
the Lower Danubian.<br />
The metaterrigenous Măgura Marga Group consisting<br />
of a prevailing quartzitic sequence, muscovite<br />
plagiogneisses, amphibolites, is highly migmatised.<br />
It was compared by Berza and Seghedi (1983) to the<br />
Lainici-Păiuș Group of the Lower Danubian.<br />
The two groups of metamorphic rocks (and others<br />
with restricted extension) are intruded by granitoid<br />
plutons (Muntele Mic, Sfârdinu, Cherbelezu,<br />
Ogradena, etc); special mention has to be made of<br />
the mafic-ultramafic Tisoviţa-Iuţi complex. The<br />
dextral Cerna-Porecˇka Reka fault system with a<br />
horizontal displacement of 40 km (trending NE) has<br />
dismembered a formerly much larger ophiolitic body,<br />
the southern part of which consists of the Deli Iovan<br />
massif of Serbia.<br />
The K-Ar model ages of samples from the Upper<br />
Danubian metamorpfic rocks and associated granitoids<br />
range between 447 and 96 M.a., demonstrating<br />
Variscan and Alpine reworking of the basement<br />
(Grünenfelder et al., 1983).<br />
Lower and Middle Paleozoic very low-grade formations<br />
are represented by the following: Nijudimu-<br />
Râu Alb Formation (Ordovician-Silurian phyllites,<br />
conglomerates, sandstones, mafic tuffs); Brustur<br />
Formation (probably Silurian conglomerates); Râul<br />
Rece-Drencova Formation (Devonian conglomerates,<br />
sandstones, slates, mafic tuffs and flows); Sevastru<br />
Formation (Lower Carboniferous limestones, slates,<br />
sandstones, mafic volcanics). With the exception of<br />
the latter which bears macrofaunal remains (Spiriferidae,<br />
etc), the ages of the former formations are<br />
constrained by palynological associations.<br />
But south of the Danube, in the Stara Planina Unit,<br />
the oldest fossiliferous formation is found as blocks<br />
in a Devonian olistostrome; its Arenigian age is constrained<br />
by Acritarchs. In the same unit, the Upper<br />
Silurian and the Devonian could be parallelized with<br />
the Drencova Formation, the age of the former being<br />
proved by Tabulate Corals.<br />
Upper Paleozoic and Mesozoic<br />
The formations overlying the Variscan and pre-Variscan<br />
basement are developed in two main zones:<br />
Sviniţa- Arjana and Cornereva-Mehadia.<br />
The following are to be mentioned: Upper Carboniferous<br />
coal-bearing conglomerates, sandstones and<br />
slates; Permian red-beds with rhyolitic volcanic<br />
and volcaniclastic rocks; Lower Jurassic coal-bearing<br />
conglomerates, sandstones and slates (“terres<br />
noires”), sometimes developed in Schela anchimetamorphic<br />
facies; Middle-Upper Jurassic, represented<br />
either by a volcano-sedimentary formation with mafic<br />
and alkaline lava flows, pyroclastic deposits, limestones<br />
and shales (Arjana), or by limestones (Sviniţa);<br />
Upper Cretaceous flysch (Arjana).<br />
The intensity of Alpine metamorphism varies in these<br />
formations between high-grade diagenesis and lowgrade,<br />
increasing eastwards.<br />
Severin Nappe. The Severin Nappe in the South<br />
Carpathians consists of obducted slices generated<br />
in a rift with oceanic or thinned continental crust,<br />
formed in the Jurassic on the European margin. It<br />
includes a Upper Jurassic tectonic melange (olistoliths<br />
of basalts, gabbros, serpentinites, harzburgites,<br />
crystalline schists, limestones, in a matrix of siliceous<br />
marly pelagic deposits-anchimetamorphic Azuga<br />
beds), and Upper Jurassic-Lower Cretaceous flysch<br />
deposits (Sinaia beds: distal limestone turbidites with<br />
a microfauna of Calpionellids). In Serbia, this unit<br />
corresponds to the Kosovica and Sub-Kosovica Nappes<br />
(Grubic´ et al., 1997).<br />
Getic Nappe Metamorphic basement.<br />
The L o t r u G r o u p represents the basement of the<br />
main part of the Getic Nappe, extending over more<br />
than 300 km in length and 80 km maximal width on
Romanian territory. It consists of a thick sequence<br />
of polymetamorphic rocks, mainly in amphibolite<br />
facies (sillimanite-kyanite-staurolite-garnet-bearing<br />
micaschists and plagiogneisses, orthogneisses, leptynites<br />
and amphibolites), as well as of dismembered<br />
ophiolitic slabs of metaperidotites, metagabbros; a<br />
siliceous manganiferous formation with tephroite<br />
concentrations; only in the deepest horizons are<br />
calcareous or dolomitic rocks found e.g. Armeniș;<br />
tectonic inclusions of anisofacial rocks-eclogites and<br />
granulites-are hosted in places). An elaborate subdivision<br />
of this group is still in progress.<br />
The bulk of K-Ar ages as well as the preliminary<br />
40 Ar / 39 Ar results “suggest that regionally penetrative<br />
high-temperature mineral assemblages and associated<br />
ductile structural elements are likely related to Late<br />
Variscan tectonothermal activity” (Dallmeyer et al.,<br />
1994). Isolated pre-Variscan mineral ages still suggest<br />
a Precambrian age of the protoliths as well as of<br />
a first metamorphism of the Lotru Group. The main<br />
part of the Getic corresponds in Serbia to the Kucˇaj<br />
Nappe and in Bulgaria to the Srednogorie.<br />
Lower and Middle Paleozoic (?) low-grade<br />
formations.<br />
The Miniș Formation is a monotonous metaterrigeneous<br />
sequence (mainly chlorite-biotite-quartzitic<br />
schists) with minor bodies of metarhyolites.<br />
The Buceava Group (Ordovician?) includes a discontinuous<br />
slab of metabasaltic rocks with associated<br />
black shales, siltites, carbonatic rocks, metapsephites<br />
and metapsammites.<br />
In Serbia, the Lotru Group corresponds to the Osanica<br />
“Series”; it is overlain by an anchimetamorphic Ordovician,<br />
beginning with Cˇaradoc, with Trilobites,<br />
Brachiopods and Acritarchs. The sequence continues<br />
with the Kucˇaj-Cernogorje Flysch (Devonian) bearing<br />
floral remains and Conodonts and with a Lower<br />
Carboniferous, both non-metamorphic (Pantic´,<br />
1963).<br />
The Sicheviţa granitoid massif (Brnjca in Serbia) is<br />
the most important of the Getic Realm, its length in<br />
the north - south direction on both sides of the Danube<br />
being about 100 km. It post-dates the Paleozoic<br />
formations in the Banat region. Two magmatic suites<br />
can be distinguished, a plagioclasic and mafic one (including<br />
trondhjemites and tonalites) and a predominantly<br />
potassic-felsitic one (including leucogranites,<br />
monzogranites, granodiorites). Isotopic age determinations<br />
gave results of 237 - 310 M.a. (K / Ar) and<br />
328 - 350 M.a. (Rb / Sr and U/ Pb).<br />
Another small granitoid intrusion in the Lotru Group,<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
e.g., is exposed at Criva (329 M.a. K / Ar) in the<br />
southern Poiana Ruscă. Older intrusions are found as<br />
orthogneiss associated with the crystalline schists.<br />
Upper Paleozoic and Mesozoic formations.<br />
The post-Variscan formations of the Getic Nappe,<br />
exposed mainly in the Reșiţa-Moldova Nouă zone,<br />
begin with Upper Carboniferous coal-bearing conglomerates<br />
and sandstones, followed by Permian<br />
black shales and red sandstones.<br />
A new transgression begins with the Lower Jurassic<br />
coal-bearing detrital sequence, continued with Middle<br />
Jurassic marls or sandstones, Upper Jurassic<br />
limestones, Lower Cretaceous marls and Urgonian<br />
limestones. The Upper Cretaceous is represented either<br />
by red marls, by a volcano-sedimentary formation<br />
(Rusca Montană basin), by sandstones and red<br />
clays with Dinosaurs (Haţeg), or as conglomerates,<br />
sandstones and marls (Vânturariţa, Olănești).<br />
Reșiţa-Sasca-Gornjak Nappe. The following structural<br />
unit is characterized by the presence of Triassic<br />
formations. In Serbia, its basement consists of an<br />
anchimetamorphic Devonian-Lower Carboniferous<br />
flysch, with Corals, Tentaculites, Orthoceratids<br />
and Pelecypods, including olistoliths with Late<br />
Silurian Orthoceratids and Crinoids (Dimitrijevic´,<br />
1997). Upper Carboniferous conglomerates and Permian<br />
black shales and red sandstones are overlain by<br />
Lower-Middle Triassic conglomerates followed by<br />
fossiliferous dolomites and limestones, the Jurassic<br />
being similar with the same formations of the Reșiţa-<br />
Moldova Nouă zone.<br />
Supragetic Nappes. The Supragetic Units can be divided<br />
in Western and Eastern ones; the former appear<br />
in Banat while the latter are exposed in the Făgăraș<br />
Mountains, east of the Olt.<br />
Western Supragetic Units Metam<br />
orphic basement.<br />
The Bocșiţ a - Drimoxa Formation consists mainly<br />
of garnet-bearing paragneisses with oligoclase porphyroblasts,<br />
and amphibolites overprinted by retrogression.<br />
It corresponds probably to a part of the<br />
Locva “Series” exposed at the entrance of the Danube<br />
into Romania. Its age could be Upper Precambrian to<br />
Lower Paleozoic.<br />
The Caraș Group includes the Naidăș-Rafnic volcano-sedimentary<br />
Formation at the base, the Dognecea-Zlatiţa<br />
terrigenous Formation and the Tâlva<br />
Mare quartzitic Formation, all exposed either in the<br />
Bocșa Massif or in the Locva Massif (SW Banat).<br />
The characteristic feature of the Caraș Group is the<br />
development of a bimodal magmatic association: rhy-<br />
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olites, gabbros, dolerites (Iancu, 1982, 1986; Iancu,<br />
Mărunţiu, 1994). The metamorphic parageneses point<br />
to a polymetamorphic history.<br />
The Moniom Group consists of the volcano- sedimentary<br />
Valea Satului Formation (Upper Devonian-<br />
Lower Carboniferous). It includes mainly mafic<br />
metatuffs with interlayered metapelitic and carbonatic<br />
rocks, scarce acid metatuffs and small bodies of gabbros<br />
and diorites-granodiorites.<br />
Their metamorphism is low-grade (Iancu, 1982;<br />
Iancu, Mărunţiu, 1994).<br />
In Serbia, the highest structural unit corresponding<br />
to the Western Supragetic is the Morava Nappe. The<br />
main part of its basement consists of the “Vlasina<br />
Series” (Dimitrijevic´, 1997). It is overlain at Bosilegrad,<br />
in south-eastern Serbia, by the anchimetamorphic<br />
Lisina beds, the Tremadocian age of which<br />
is constrained by Brachiopods. Consequently, the<br />
Vlasina Series could be compared to the Locva “Series”<br />
or to the Bocșiţa-Drimoxa Formation.<br />
Mesozoic formations. The Bocșiţa-Drimoxa Formation<br />
is overlain, west of Reșiţa, by limestones, the<br />
age of which could be ascribed to the Upper Jurassic-<br />
Lower Cretaceous.<br />
E a s t e r n S u p r a g e t i c U n i t s. M e t a m o r p h i c b a s e m<br />
e n t. East of the Olt, the Supragetic basement is represented<br />
mainly by two groups: Cumpăna and Făgăraș.<br />
The C u m p ă n a G r o u p is composed of the Cumpăna<br />
linear Gneiss (originating in a polymetamorphic granite),<br />
the Cozia Augengneisses and the Măgura Câinenilor<br />
Micaschists (+ kyanite, staurolite).<br />
The F ă g ă r a ș G r o u p consists of a sequence of micaschists,<br />
crystalline limestones and dolomites, para-amphibolites<br />
and graphite schists; an intensive retrogressive<br />
overprint developed over large areas.<br />
The L e a o t a G r o u p is considered by Săndulescu<br />
(1984) and others as belonging to the Getic Nappe. Its<br />
sequence consists of the Voinești Formation (Upper<br />
Precambrian, according to palynological data), similar<br />
to the Bocșiţa-Drimoxa Formation, the Bughea<br />
Amphibolite, the Lerești Formation (definitely Lower<br />
Ordovician, according to palynological data) of albite-porphyroblast<br />
schists and albite gneisses and the<br />
Călușu Formation (Devonian ?) consisting of greenschists.<br />
The Bughea Amphibolite is intruded by the<br />
Albești Granite (473-486 M.a., K / Ar).<br />
Serbo-Macedonian Massif. The Serbo-Macedonian<br />
massif falls outside our observation area. It is considered<br />
by some authors (Săndulescu, 1984; Dimitrijevic´,<br />
1997) as part of the same structural unit as the<br />
Supragetic. However the two units are separated by a<br />
major shear zone (Dusˇanovo, Rozaj-Bovan or Vrvi<br />
Kobila line, Kräutner, Krstic´, 2002). North of the<br />
Danube, the western parts of the Vrsˇac (Serbia) and<br />
Buziaș (Romania) crystalline “islands” belong to the<br />
Serbo-Macedonian massif str.s.<br />
Main tectonic features. Similarly to the South<br />
Apusenides, the geotectonic evolution of the South<br />
Carpathians was polyphasic: 1) During the Mesocretaceous<br />
tectogenesis, the Getic Nappe was overthrust<br />
onto the Severin Nappe. 2) During the Laramian tectogenesis,<br />
the Severin Nappe bearing the Getic Nappe<br />
“piggy-back” was overthrust onto the Danubian (Codarcea,<br />
1940). The overthrust of the Upper Danubian<br />
onto the Lower Danubian as well as that of the Western<br />
Supragetic onto the Getic probably belong to the<br />
first phase. Each of the main Alpine units described<br />
above is complicated by pre-Variscan, Variscan and<br />
even Alpine subunits. The age of overthrust of the<br />
Eastern Supragetic is controversial.<br />
B a n a t i t i c L a t e C r e t a c e o u s m a g m a t i s m. In the<br />
Romanian South Carpathians, the Upper Cretaceous<br />
magmatism was mainly intrusive and developed<br />
along three lineaments; it is represented by calc-alkaline<br />
plutons (granodiorites, granites, diorites) as well<br />
as by hypabissal minor intrusions of porphyry quartzdiorites,<br />
monzogranites, andesites, dacites, rhyolites<br />
and lamprophyres. Only in the Rusca Montană Upper<br />
Cretaceous basin overlying both the Getic and Supragetic<br />
an andesitic volcano-sedimentary formation<br />
is exposed. Isotopic K / Ar ages are comprised between<br />
91 and 65 M.a. (Berza et al., 1998).<br />
Field itinerary<br />
DAY 1<br />
Suceava - Gura Humorului - Câmpulung Moldovenesc<br />
- Vatra Dornei<br />
Aims : This is one of the northernmost profiles (excepting<br />
the Maramureș) across the whole East Carpathian<br />
structure. Along it there is the possibility to<br />
examine the Subcarpathians, the Flysch Zone and the<br />
Central East Carpathians (with their superposed nappes).<br />
The XV th century frescoed Voronet monastery<br />
will be visited.<br />
From Suceava the fieldtrip leaves toward the west,<br />
following main road no. 17. Until Păltinoasa, about<br />
30 km from Suceava, the Sarmatian formations of the<br />
Foreland will be crossed. At Păltinoasa, the frontal<br />
part of the Flysch nappes is well expressed.
Stop 1.1:<br />
Păltinoasa Quarry.<br />
On the left-hand bank of the Moldova, at Păltinoasa,<br />
a sequence crops out of the Lutetian - Bartonian formations<br />
of the Păltinoasa “Rabotage” Slice. The most<br />
important part of this sequence is represented by the<br />
Păltinoasa Sandy Limestone of Lutetian age (Ionesi,<br />
1971). It is equivalent to the Paszieczna and Doamna<br />
limestones (see Tab.I). On the top of the quarry, above<br />
the Păltinoasa Sandy Limestone, lies the Strujinoasa<br />
Formation, a variegated shaly - clayey formation, in<br />
which red - purple clays are dominant. The Lutetian<br />
/ Bartonian stratigraphic boundary is situated within<br />
the Strujinoasa Formation.<br />
Upstream, in the town of Gura Humorului, the front<br />
of the Tarcău Nappe will be crossed. In front of<br />
the Tarcău Nappe the Păltinoasa “Rabotage” Slice<br />
is situated. Furthermore, all along the front of the<br />
unit such “rabotage” slices are common, until the<br />
East Carpathians Bending Area (Vrancea Mts.). In<br />
the Gura Humorului area boreholes situated on the<br />
external part of the Tarcău Nappe, penetrated in the<br />
Păltinoasa “Rabotage” Slice and, crossing a narrow<br />
Subcarpathian Nappe, reached the underthrust<br />
Foreland, there represented mostly by the Scythian<br />
Platform. Similar geological situations were drilled<br />
northward in the Putna Valley (near the Roumanian /<br />
Ukrainian boundary).<br />
Stop 1.2:<br />
Voronet.<br />
In Voroneţ, along the river with the same name, the<br />
Paszieczna Limestone (Lutetian) crops out. It is a<br />
pelagic lithographic white-yellowish limestone, with<br />
cherts and, sometimes, with resedimented Nummulites.<br />
They are followed by the Plopu Formation (see<br />
the next stop).<br />
In the southern part of the village the Voroneţ Monastery,<br />
founded in the XV th century by Stephen the<br />
Great, Prince of Moldavia, will be visited. The outer<br />
and the inner walls are covered by frescoes.<br />
Stop 1.3:<br />
West of Gura Humorului.<br />
At 1.6 km upstream from the western end of Gura<br />
Humorului a profile open on the left-hand bank of the<br />
Moldova allows us to examine the Lutetian-Rupelian<br />
succession, specific for the external part of the Tarcău<br />
Nappe (Suceviţa lithofacies). Above the Lutetian<br />
Paszieczna Limestone, follows the two-component,<br />
dense rhythmically turbiditic sequence (“hieroglyphic<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
beds-type flysch”) of the Plopu Formation<br />
(Uppermost Lutetian-Priabonian). Red and purple<br />
clayey shales (an equivalent of the Strujinoasa Formation)<br />
are inlayered in the lower third. The Eocene<br />
/ Oligocene boundary is situated within a sandstone<br />
sequence (Săndulescu et al., 1987). The lower part<br />
of it - the Lucăcești Sandstone - shows inlayerings<br />
of “Globigerina marls” (white compact marls rich in<br />
planktonic microfauna, nanoplankton and silicoflagellates<br />
of Late Priabonian age), while the upper part<br />
- the Fierăstrău Sandstone – has inlayerings of dark<br />
bituminous siltstones and/or clays (containing nanoplankton<br />
and silicoflagellates of Earliest Rupelian).<br />
The sandstones are both orthoquartzitic (oligomictic),<br />
the Lucăcești one also containing grains of glauconite.<br />
The Lower Menilites with Brown Marls is the<br />
next lithostratigraphic unit. It is built up by well-layered<br />
bituminous silicolites (menilites), which proceed<br />
from the diagenesis of the Diatomaea rich muds.<br />
Dark brown bituminous marly limestones (the so<br />
called “Brown Marls”) are associated with the Lower<br />
Menilites. Very thin intercalations of bituminous<br />
clays or siltstones also occur. The Lower Dysodilic<br />
Shales follow between the Lower Menilites and the<br />
Kliwa Sandstone. They are dark-coloured bituminous<br />
clays or clayey siltstones, very thinly layered in submm.<br />
sheets (“paper-sheeted”). Intercalations of cm. to<br />
decimeter-fine quartzitic sandstones occur. Massive<br />
orthoquartzitic sandstones – Kliwa Sandstone - develop<br />
in the top of the succession of this outcrop. The<br />
quartzitic grains of the Kliwa Sandstone are of aeolian<br />
origin, subsequently transported and resedimented in<br />
the outer part of the Moldavidian sedimentary basin.<br />
The source of this detrital material was situated in<br />
the Foreland, a conclusion documented by the lithic<br />
fragments of “Green Schists” (Dobrogean type) included<br />
in the arenites. Of the same origin as the Kliwa<br />
Sandstone are also the Lucăcești and the Fierăstrău<br />
sandstones. The first three lithostratigraphic units of<br />
the Oligocene belong to the Rupelian. The boundary<br />
between the Rupelian and the Chattian runs within<br />
the Kliwa Sandstone. The complete succession of<br />
the “Bituminous Lithofacies with Kliwa Sandstone”<br />
above the Kliwa Sandstone consists of: the Upper<br />
Dysodilic Shales (the Oligocene/Miocene boundary<br />
runs within their lithostratigraphic unit), the Upper<br />
Menilites (without “Brown Marls”), the Goru-Mișina<br />
Formation (coarse-grained rocks rich in “Green<br />
Schists” debris), the (lower) Evaporitic Formation<br />
(Burdigalian) (Săndulescu and Micu, 1988).<br />
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Leader: M. Sandulescu<br />
Stop 1.4:<br />
Frasin.<br />
The locality of Frasin is situated at the confluence<br />
of Suha Bucovineană with the Moldova. On the<br />
left-hand (northern) bank of Moldova, in an imbricated<br />
structure, also belonging to the Tarcău Nappe,<br />
several Senonian and Paleocene sequences crop out.<br />
The Hangu Formation is a Senonian calcareous<br />
turbiditic (flysch) formation. Two-components (limy<br />
arenites/marls) or three-components (limy arenites/<br />
marls/marly or lithographic limestones) rhythms are<br />
developed. The graded-bedded arenites show at their<br />
basal part grains of “Green Schists”, limestones and<br />
fragments of Inoceramus. Ammonites, inocerams<br />
and a rich pelagic foraminifer assemblage (Ion-<br />
Săndulescu, 1975; Antonescu et al., 1989) document<br />
the Senonian age for the Hangu Formation. The Paleocene<br />
is represented by the Putna Formation. This is<br />
a sandy/marly flysch with a two-component rhythms<br />
in which the sandstones are rather dominant in thickness.<br />
The arenitic material is of polymictic type (as<br />
for the Hangu Formation) containing “Green Schists”<br />
too. The Paleocene age (Antonescu et al., 1989) is<br />
supported by a rich pelagic microfauna and by scarce<br />
examples of Dyscocyclina. The Straja Formation is<br />
younger than the Putna one. It is a variegated flysch<br />
built up by two-component rhythms in which the<br />
arenites are polymictic, with a silica matrix and the<br />
pelites are red-purplish, green and grey. Glauconite<br />
may be frequent in the sandstones. The age of this<br />
formation is (according to the microfaunal content)<br />
Uppermost Paleocene-Lower Ypresian. The source<br />
area for the Straja arenites is external (Foreland), as<br />
well as for the whole Cretaceous-Paleogene-Lower<br />
Miocene succession of the external part of the Tarcău<br />
Nappe as well as those of the Marginal Folds and<br />
Subcarpathian nappes.<br />
Stop 1.5:<br />
Vama.<br />
The locality of Vama is situated in an area corresponding<br />
to the inner subunit (digitation) of the Tarcău<br />
Nappe, the Vama Digitation respectively. On both<br />
banks of the Moldova River the Paleogene formations<br />
of the digitation crop out. The oldest sequence (cropping<br />
out) is the Moldoviţa Sandstone. It represents a<br />
sandy flysch with mica-rich arenites, which prevail in<br />
respect to the clayey pelites, within two-component<br />
rhythms of 30-100 cm. The arenitic material proceeds<br />
from an internal (Carpathian) source situated<br />
in the Central-East Carpathians and the innermost<br />
nappes (Black Flysch, Ceahlău) of the Flysch Zone.<br />
The age, according to the agglutinated foraminifera<br />
associations, is Lower-Middle Eocene, possibly uppermost<br />
Paleocene also. Some red-purplish shales are<br />
inlayered at different levels. Above the Moldoviţa<br />
Sandstone follows the Plopu Formation (see Stop<br />
1.3). The Lower Oligocene sequences are developed<br />
in two lithofacies. In the external scales of the Vama<br />
Digitation, above the Plopu Formation, the Lower<br />
Menilites and the Lower Dysodilic Shales crop out,<br />
as in the more external zones (see above). In the inner<br />
scale of the Vama Digitation above the Plopu Formation<br />
the “Shaly Horizon” with grey, dark-grey and<br />
blackish clays and silts, thin sandstone inlayering and<br />
also rare, sideritic pelagic limestones are developed.<br />
It is an equivalent of the Lower Menilites and Lower<br />
Dysodilic Shales. In the inner parts, the Fusaru Sandstone<br />
follows. This is a massive, micaferous sandstone,<br />
lithologically similar to the Tarcău Sandstone,<br />
proceeding from the same source area (Carpathian).<br />
In the outer part of the Vama Digitation the Fusaru<br />
Sandstone is mixed with Kliwa Sandstone, stressing<br />
out their interfingering. The youngest sequence is<br />
the Vineţișu Formation, a two-component flysch<br />
with limy arenites, often convolute, and marls. The<br />
Oligocene/Lower Miocene boundary runs within it<br />
(fide Săndulescu et al., 1995).<br />
In Prisaca Dornei the front part of the Audia Nappe,<br />
which overthrusts the Tarcău one, is well expressed<br />
in relief.<br />
Stop 1.6:<br />
West of Prisaca Dornei.<br />
On the left-hand bank of the Moldova River, 700<br />
m west of the western border of Prisaca Dornei village,<br />
massive sandstones representing the Prisaca<br />
Sandstone crop out. This is the youngest formation<br />
of the Audia Nappe in this area; its age is Maastrichtian-Lutetian<br />
(Săndulescu et al., 1992). The arenitic<br />
material of the Prisaca Sandstone, polymictic, rich,<br />
mica-bearing, proceeds from the Carpathian source.<br />
In the analysed outcrop it is possible to observe “soft<br />
pebbles” (“galets mous”) of “Black Shales” reworked<br />
by the fluxoturbiditic currents - perhaps in submarine<br />
canyons - from the Lower Cretaceous “Black Shale”<br />
Formation of the same sedimentary basin. 100-200 m<br />
downstream from the outcrop slided variegated shales<br />
may be observed which represent the condensed sequence<br />
of the Vraconian-Lower Senonian (the “Variegated<br />
Clay” Formation) situated between the Prisaca<br />
Sandstone and the “Black Shale” Formation.
The town of Câmpulung Moldovenesc, about 10 km<br />
long, develops along the Moldova Valley, more or less<br />
parallel to the tectonic structures.<br />
Stop 1.7:<br />
Câmpulung Moldovenesc – Izvorul Alb brook.<br />
The frontal part of the Bucovinian Nappe is well exposed<br />
in the lowermost part of the Izvorul Alb Brook,<br />
at the periphery of the town. At the same time it corresponds<br />
with the anticlinorium which limits the external<br />
limb of the Rarău Syncline. In the Izvorul Alb<br />
brook a complex of anticline folds are marked by the<br />
outcropping of the Anisian massive dolomites (shallow<br />
water, with intratidal “cracking breccia” zones).<br />
With a large erosional gap the Pojorâta Formation,<br />
which is a two-component flysch sequence, 700-800<br />
m thick, follows. The arenites are polymictic (subgreywackes)<br />
with limy or marly matrix, the lutites are<br />
marls. Red and yellowish marly pelagic limestones<br />
are intercalated at different levels. The age of the<br />
Pojorâta Formation is Tithonian-Neocomian, stressed<br />
by their Tintinnides and Aptychus content (Lamellaptychus<br />
beyrichi, L. beyrichi var. fractocostata and<br />
Lamellaptychus gr.A and Calpionella alpina, C. elliptica,<br />
Tintinopsella carpathica - cf. Turculeţ, 1971;<br />
Săndulescu, 1973; Săndulescu et al., 1976). Above<br />
one of the dolomitic anticlinal cores, between them<br />
and the Pojorâta Formation, red-purplish silts may be<br />
observed. They may be an equivalent of the “Radiolarite<br />
Beds” of Callovian-Oxfordian age, which in<br />
other areas of the Rarău Syncline are well developed.<br />
The filling of the Rarău Syncline and consequently,<br />
the youngest sedimentary formations of the Bucovinian<br />
Nappe, is represented by the Wildflysch Formation<br />
of (Upper Barremian ??) Aptian-Albian age (Mutihac<br />
and Bratu, 1965; Săndulescu, 1975). It can be examined<br />
along several km in the Izvorul Alb Brook, upstream<br />
of the confluence with the Limpede Brook (the<br />
dolomites quarry). Wildflysch is a mixed formation<br />
with a dark-coloured, clayey or siltic-clayey matrix<br />
in which sedimentary klippen from different rocks of<br />
different ages are incorporated, but all older than the<br />
matrix. In the Bucovinian Wildflysch Formation the<br />
sedimentary klippen – of very different sizes - belong<br />
to the different lithofacies of the Transylvanian Nappes<br />
(basic and ultrabasic rocks, Middle and Upper<br />
Triassic limestones and dolomites, Lower and Middle<br />
Jurassic sandy-marly rocks, Upper Jurassic-Neocomian<br />
and Urgonian (Barremian) massive limestones)<br />
(Săndulescu, 1975, 1976; Săndulescu et al., 1981).<br />
The sedimentation of the Wildflysch Formation<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
precedes the “arrival” – at the end of the Albian - of<br />
the Transylvanian Nappes, the sedimentary klippen<br />
involved within the wildflysch proceeding from the<br />
front of the nappes in movement.<br />
From the Izvorul Alb Brook or from the suburbs,<br />
downstream from the town of Câmpulung Moldovenesc<br />
it is possible to see the Rarău Mts. The white<br />
cliffs which are visible correspond to the Middle Triassic<br />
dolomites and the Urgonian limestones, tectonic<br />
outliers of the Transylvanian nappes.<br />
Stop 1.8:<br />
West Sadova.<br />
On the left-hand bank of the Moldova River, 120 m<br />
west of the railway/national road crossing, an anticline<br />
of the Bucovinian Nappe can be examined, marqued<br />
by the outcropping of the “Aptychus Beds” Formation<br />
of Tithonian-Valanginian age. This formation consists<br />
of well bedded, white, yellowish, grey or red-purplish<br />
lithographic limestones, sometimes with cherts. Typical<br />
assemblages of Tintinnides (Calpionella alpina,<br />
C. elliptica, Crassicolaria massutiniana, C.parvula<br />
followed by Tintinopsella carpathica, Calpionellites<br />
darderi and Calpionellopsis simplex - Săndulescu,<br />
1976) corroborated with the Aptychus fauna (Turculeţ<br />
1971) support the above-mentioned age. The “Aptychus<br />
Beds” Formation is, more or less, a stratigraphic<br />
equivalent of the Pojorâta Fm., but with a more<br />
internal position, stressing that the arenitic material<br />
of the latter has an external source in respect to the<br />
paleogeographic position of the Bucovinian Nappe,<br />
the source being situated in the area corresponding<br />
paleogeographically to the Subbucovinian Nappe. On<br />
the western limb of the complex anticlinal structure of<br />
West Sadova the Muncelu Sandstone (conglomerates<br />
and coarse grained sandstones outcropping in a large<br />
quarry) of Hauterivian age, develops. This Sandstone<br />
is recorded also, slighty discordant (?) above the Pojorâta<br />
Formation.<br />
The Wildflysch Formation constitutes, normally, the<br />
filling of the Rarău Syncline, but with an asymmetrical<br />
position: the post-Triassic formations known on<br />
the outer limb of the syncline are absent on the inner<br />
one where the wildflysch lies directly on the Triassic<br />
dolomites and the “Radiolarite Beds”, both cropping<br />
out in Pojorâta in several quarries. From Pojorâta<br />
the fieldtrip follows the Moldova Valley upstream to<br />
Breaza. In this tract the road crosses the metamorphic<br />
formations of the Bucovinian Nappe and, once more,<br />
the Rarău Syncline.<br />
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Stop 1.9:<br />
Breaza Ultramafic Tectonic Outlier (the visit of the<br />
Breaza tectonic outlier will be conditioned by the<br />
time and weather situation). Above the Wildflysch<br />
Formation of the northen sector of the Rarău Syncline,<br />
ultramafic rocks which represent a tectonic outlier of<br />
the Transylvanian nappes are developed (Săndulescu,<br />
1973; Săndulescu and Russo - Săndulescu, 1981). It<br />
is located in the axis of the syncline, which has an<br />
asymmetric shape in this area, with the external limb<br />
less developed than the internal one. On a left-hand<br />
tributary of the Moldova River, in Breaza, in front<br />
of the church, the following cross-section may be<br />
examined: on the first 300 m the Sinaia Formation<br />
of the Ceahlău Nappe (Tithonian-Neocomian calcareous<br />
flysch) crops out; it is overthrust by the metamorphic<br />
rocks of the Bucovinian Nappe, overlapped<br />
by Anisian dolomites and Callovian-Oxfordian (?)<br />
(or Ladinian?) “Radiolarite Beds”; the Wildflysch<br />
Formation, as a rule, represents the filling of the syncline.<br />
On the summits situated north of the brook the<br />
peridotites and serpentinites of the Breaza Tectonic<br />
Outlier crop out. This nappe outlier may be an equivalent<br />
of the Olt Nappe, which also contains ultramafic<br />
rocks of Ladinian/Carnian age. Further northward<br />
in the Păltiniș Summit conglomerates and coarsegrained<br />
sandstones of Cenomanian age are preserved<br />
from erosion. They seal the tectonic contacts between<br />
the Transylvanian and Bucovinian nappes and between<br />
the latter and the Ceahlău Nappe.<br />
The field-trip returns to Pojorâta and enters the Putna<br />
Brook (left tributary of Moldova River). Both slopes<br />
of the Putna Valley consist of metamorphic rocks of<br />
the Tulgheș Series, which belongs to the Bucovinian<br />
Nappe. At 4 km along the Putna Valley within a<br />
tectonic window the sedimentary formations of the<br />
Subbucovinian Nappe are exposed.<br />
Stop 1.10:<br />
Putna Valley Tectonic Window. The oldest formations<br />
cropping out are the Anisian dolomites. Thin red<br />
siliceous silts, possibly Ladinian, certainly Triassic,<br />
cover the dolomites. The youngest sequence known in<br />
the window are Lower Jurassic (according to the silicoflagellate<br />
assemblages) limonitic sandstones with<br />
blackish siltstone intercalations. The Subbucovinian<br />
sedimentary rocks are tectonically overlapped, at 50<br />
m above the brook, on its slopes, by the Tulgheș<br />
Series formations. Massive metamorphosed dolomites,<br />
which may belong to the Rebra Series, tectonically<br />
transported at the base of the Tulgheș<br />
Series, can be examined at the eastern border of the<br />
window. In the thalweg of the Putna brook, in front<br />
of a small tributary, a thin bank of graphite quartzites<br />
and schists crop out. The rocks belong to the “Median<br />
Complex” (Tg2) of the Tulgheș Series. Descriptions<br />
after Kräutner in: Sndulescu et al., 1981. The western<br />
border of the window is a vertical fault with a displacement<br />
of about 500 m (controlled by a borehole<br />
situated 100 m west of the fault). The borehole was<br />
drilled in the Bucovinian Nappe and reached the Subbucovinian<br />
Anisian dolomites.<br />
The fieldtrip continues upstream, westward. At the<br />
Valea Putnei Railway Station the erosional contour<br />
of the Bucovinian Nappe is stressed by the tectonic<br />
superposition of the metamorphic formations of the<br />
nappe above the Subbucovinian sedimentary formations<br />
which shows the same lithostratigraphic succession<br />
as in the Valea Putnei Tectonic Window.<br />
In the Mestecăniș Pass (1083 m in altitude), which is<br />
reached 5 km west of Valea Putnei Railway Station, a<br />
beautiful view opens out on the Bistriţa Mts. and the<br />
Bistriţa Aurie Valley, where the deepest Central East<br />
Carpathains unit, the Iacobeni Nappe, the highest of<br />
the Infrabucovinian nappes crops out within a tectonic<br />
window.<br />
From the Valea Putnei Railway Station up to<br />
Mestecăniș Pass and from there down until the western<br />
margin of the Mestecăniș Village, the road crosses<br />
the Tulgheș Series of the Subbucovinian Nappe.<br />
Stop 1.11:<br />
Puciosu Valley Cross Section.<br />
Along the national road, which runs on the righthand<br />
slope of Puciosu Brook, the basal sequence<br />
of the Subbucovinian Nappe and the sedimentary<br />
formations of the Iacobeni Infrabucovinian nappe<br />
are exposed. Upstream-downstream it is possible to<br />
examine: (1) the Black Quartzitic Formation (TG2)<br />
of the Tulgheș Series of the Subbucovinian Nappe<br />
(Bercia et al., 1975) represented by sericitic-quartzitic<br />
and chloritic-graphitic schists, with two levels of<br />
black quartzites; thin intercalations of metabasalts<br />
or limestones and calcschists, are known, south and<br />
north of Puciosu Brook. The black quartzites mark the<br />
level of syngenetic manganese ores, which consist of<br />
Mn-carbonate and silicates, enriched in Mn-oxydes in<br />
the oxidation zone. The principal mines are located<br />
some kilometers southwards; (2) the “Argestru Formation”<br />
(see also below), built up of metapsammites<br />
and phyllites with intercalations of metabasalts; (3)<br />
weak bituminous (“stinking”) Anisian dolomites
and limestones. Up on the slope, with a large stratigraphic<br />
gap, Middle Jurassic limy sandstones follow<br />
(Săndulescu, 1976).<br />
Before the first houses in the Iacobeni locality, downstream<br />
from a right-hand tributary, a small window<br />
of Infrabucovinian Anisian dolomites are exposed<br />
underneath the metamorphic rocks of the “Argestru<br />
Formation”. The western border of the window is a<br />
vertical fault. About 350 m downstream the well-layered<br />
Anisian dolomites crop out in a large quarry. At<br />
its uppermost part, massive dolomites seem to cover<br />
the layered dolomites with tectonic disconformity.<br />
Downstream, west of the large dolomite quarry,<br />
towards the Bistriţa Aurie River, blocks and fragments<br />
of Lower Triassic quartzitic sandstones<br />
and conglomerates as well as purplish siltic clayey<br />
shales occur. Near the confluence between Puciosu<br />
Brook and the Bistriţa Aurie River, along the road to<br />
Ciocănești, an outcrop of muscovite-quartz schists<br />
with chloritised biotite can be examined. It is ascribed<br />
to the Bretila Series, which also crops out several<br />
hundreds of meters upstream on the left-hand bank<br />
of the river, where gneisses may be recognized too.<br />
In the metamorphic schists axes of mesoscopic folds<br />
trend N 20 W / 10 NW. Descriptions after Kräutner in:<br />
Săndulescu et al., 1981.<br />
The tectonic framework and the age of the “Argestru<br />
Formation” was subject of controversy. Firstly it was<br />
considered a lithostratigraphic Paleozoic unit which<br />
builds up an independent tectonic unit (“Argestru<br />
Unit”) situated between the Subbucovinian Nappe<br />
and the Infrabucovinian nappes. Afterwards the “Argestru”<br />
sequence was considered an equivalent of the<br />
Rebra Series or later of the Bretila Series, squeezed<br />
in both interpretations at the base of the Subbucovinian<br />
Nappe (Kräutner, 1980, 1988; Balintoni, 1985,<br />
1997).<br />
DAY 2<br />
Vatra Dornei – Bicaz - Lacul Roșu - Gheorghieni<br />
- Miercurea Ciuc<br />
Aims: Along the Bistriţa Valley, south-east of Vatra<br />
Dornei, the formations which built up the inner units<br />
of the Flysch Zone (the Ceahlău, Convolute Flysch<br />
and Audia nappes) can be examined, as well as the inner<br />
part of the Tarcău Nappe. In the upper Bicaz Valley<br />
the Hăghimaș Syncline (Bucovinian Nappe and<br />
Hăghimaș Transylvanian Nappe) will be crossed.<br />
From Vatra Dornei the fieldtrip follows the Bistriţa<br />
valley downstream. Until Broșteni it crosses the<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Central East Carpathians nappes (Crystalline-Mesozoic<br />
Zone). The Infrabucovinian, Subbucovinian<br />
and Bucovinian nappes crop out represented by their<br />
metamorphic formations.<br />
Stop 2.1:<br />
Broșteni-Cotârgași.<br />
At the downstream margin of Broșteni and 700 m<br />
upstream, the confluence of Cotârgași Brook with the<br />
Bistriţa River, the frontal contour of the Bucovinian<br />
Nappe crosses the Bistriţa Valley. 200 m upstream<br />
of this contour a small tectonic window is opened<br />
in the metamorphic formations of the nappe; within<br />
this window Anisian dolomites crop out. They belong<br />
to the sedimentary sequence of the Subbucovinian<br />
Nappe. The dolomites were transported as a tectonic<br />
outlier (“lambeau de charriage”) by the Bucovinian<br />
Nappe. Such situations are frequent all along the frontal<br />
contour of the Bucovinian Nappe (see also Stop<br />
2.10). Downstream from the front of the Bucovinian<br />
Nappe the innermost unit of the Flysch Zone – known<br />
in this area - crops out. It is the Cotârgași Unit (Scale).<br />
The Cotârgași Formation can be examined in a large<br />
outcrop where well-bedded pelagic micritic or marly<br />
limestones are exposed; they show relatively rare intercalations<br />
of polymictic graded bedded sandstones.<br />
In the Cotârgași Formation at different levels and with<br />
different thicknesses, polymictic (amphibolites, micaschists,<br />
chloritic phyllites, quartzites, Triassic and/<br />
or Jurassic dolomites and limestones) limy breccias<br />
and/or microbreccias, are inlayered. From the lower<br />
and middle part of the formation poor Tintinnide associations<br />
(with Calpionella alpina, C.elliptica, Tintinopsella<br />
carpathica) stress the Tithonian-Neocomian<br />
age. The upper third, where the breccias prevail, may<br />
be Hauterivian or even Barremian.<br />
Following its tectonic position between the Central<br />
East Carpathian nappes and the Ceahlău one, the<br />
Cotârgași Unit may be correlated with the Baraolt<br />
Nappe known southward in the inner Bend Area. In<br />
fact the lithofacies of the Cotârgași Formation shows<br />
some similarities with the isochronous sequences of<br />
the Baraolt Nappe.<br />
The fieldtrip proceeds downstream. For more than 20<br />
km the Bistriţa Valley crosses the Sinaia Formation<br />
of the innermost sub-unit (digitation) of the Ceahlău<br />
Nappe, the Ciuc Digitation respectively.<br />
Stop 2.2:<br />
Sinaia Formation in the Bistriţa Valley.<br />
The Sinaia Formation (4-5 km in thickness) is a<br />
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calcareous flysch, with turbiditic two- and three-component<br />
rhythms (limy sandstone / marls, silty marls<br />
/ marly limestones, limy sandstones / marls / marly<br />
limestones), 25-75 cm thick. The sandstones are polymictic,<br />
the marly limestones are pelagic, micritic,<br />
containing Tintinnides at different levels. Generally,<br />
taking into account the whole Ceahlău Nappe, the<br />
Sinaia Formation can be divided into three members.<br />
The lower one is dominantly pelitic (marls and siltic<br />
marls) with inlayerings of marly pelagic limestones<br />
and scarce sandstones. In the limestones Calpionella<br />
alpina (frequent) and C.elliptica were found, the<br />
age considered as Tithonian. The median member<br />
shows the typical lithofacies of the Sinaia Formation<br />
(see above) and represents 75-80% of its thickness.<br />
The presence of Calpionella elliptica, Tintinopsella<br />
carpathica, Calpionellites div.sp. was determined,<br />
supporting the Berriasian-Valanginian age. The Upper<br />
Member , Hauterivian in age (with Peregrinella<br />
peregrina), is represented by a two-component flysch<br />
(limy sandstones and dark coloured marls) characterized<br />
by inlayerings of limy polymictic breccias (meso-<br />
and epizonal metamorphics, Triassic and/or Jurassic<br />
dolomites and limestones, quartzitic sandstones). The<br />
Sinaia Formation shows frequent diaclases filled with<br />
calcite and also some zones of schistosity.<br />
Stop 2.3:<br />
Ugra Formation at Săvinești locallity.<br />
The Barremian-Aptian formations of the Ciuc Digitation<br />
are represented by a turbiditic and fluxoturbiditic<br />
sandy flysch – the Ugra Formation. In the 30-150 cm<br />
thick, two-component rhythms, sandstones (65-90 %)<br />
prevail over marls or silty marls. The arenitic material<br />
is polymictic (subgreywacke-type) (quartz and<br />
quartzites, meso- and epizonal metamorphics, Triassic<br />
and Jurassic limestones and dolomites, as well as<br />
mafics and ultramafics) its source area being situated<br />
inward relative to the sedimentary trough.<br />
Downstream of Săvinești near Topliceni the field trip<br />
enters the Durău Digitation, external in respect to the<br />
Ciuc one. The specific formations of this sub-unit of<br />
the Ceahlău Nappe, above the Sinaia Formation, are<br />
the Piscu cu Brazi Formation and the Ceahlău Conglomerates.<br />
Stop 2.4:<br />
Piscu cu Brazi Formation at Poiana Teiului.<br />
On the right-hand bank of the Bistriţa River, 1 km upstream<br />
of the large viaduct from Poiana Largului, and<br />
also on the western bank of (antropic) Bicaz Lake,<br />
the Piscu cu Brazi Formation crops out. It is a twocomponent<br />
flysch, with rhythms 10-50 cm thick. The<br />
sandstones are polymictic (same composition as the<br />
Ugra sandstones – see above), the pelitic component<br />
is marly or silty marly. Toward its upper part the Piscu<br />
cu Brazi Formation grows more massive with 0.5-1.5<br />
m of sandstone (Poiana Maicilor Sandstones). The<br />
age of the Piscu cu Brazi Fm. is Barremian-Aptian according<br />
to the different ammonitic faunas recorded at<br />
different levels (fide Săndulescu, 1990). The Poiana<br />
Maicilor Sandstones are developed in the Upper Aptian.<br />
The youngest formation of the Durău Digitation<br />
are the Albian Ceahlău Conglomerates, which built<br />
up the Ceahlău Mts., visible south of Bicaz Lake.<br />
At Poiana Teiului a calcareous isolated rock is situated<br />
at the northern end of Bicaz Lake (near the viaduct). It<br />
is built up of Urgonian limestones with Pachyodonta<br />
and Orbitolina (Barremian-Lower Aptian) and represents<br />
a tectonic slice, pulled out from the outer margin<br />
of the Outer Dacidian trough – the Peri-Moldavian<br />
Cordillera - and transported to the base of the Ceahlău<br />
Nappe. From Poiana Teiului the fieldtrip proceeds<br />
along the north-eastern slope of Bicaz Lake.<br />
Stop 2.5:<br />
Frontal contact of the Ceahlău Nappe / Convolute<br />
Flysch Nappe.<br />
About 4 km downstream from the Poiana Teiului<br />
viaduct, the fieldtrip reaches the erosional contour<br />
of the tectonic contact between the outernmost part<br />
of the Ceahlău Nappe and the youngest formations<br />
of the Convolute Flysch Nappe. Massive micaferous<br />
sandstones representing the outermost sub-unit of the<br />
Ceahlău Nappe (? the Bodoc Digitation) is overthrust<br />
above the Upper Convolute Flysch Member (twocomponent<br />
turbiditic rhythms, 10-20 cm, with more<br />
or less frequent inlayerings of red marls). The age of<br />
this lower sequence of the Upper Convolute Flysch<br />
Member is Vraconian-Cenomanian; in some other<br />
areas of the East Carpathians, where this Member<br />
is fully developed, the micropaleontological assemblages<br />
specified a Vraconian-Lower Senonian age<br />
(Săndulescu J., 1976; Antonescu and Săndulescu,<br />
1985; Săndulescu et al., 1993).<br />
Stop 2.6:<br />
Cotumba Sandstone and Leţești Conglomerates.<br />
About 1.6 km downstream along the national<br />
route, massive sandstones with conglomerates and<br />
microconglomerate intercalations crop out. The massive<br />
sandstones represent the Cotumba Sandstone
situated at the middle part (Middle- and a part of the<br />
Upper Albian) of the Convolute Flysch Formation. It<br />
is a quartzitic-micaferous sandstone, graded bedded<br />
or with fluxoturbiditic features, showing thin to very<br />
thin (joints) intercalations of dark or grey marls. The<br />
Leţești Conglomerates develop as lenses of different<br />
sizes within the Cotumba Sandstone. They are dominantly<br />
quartzitic, with few lithic fragments represented<br />
by metamorphic schists. The source area of the<br />
Cotumba Sandstone and of the Leţești Conglomerates,<br />
as well as for all arenites of the Convolute Flysch<br />
– represented by the Peri-Moldavian Cordillera - are<br />
situated on the inner border of the Convolute Flysch<br />
sedimentary trough.<br />
Stop 2.7:<br />
Lower Convolute Flysch Member at Chiriţeni.<br />
3.5 km downstream from the preceding stop, several<br />
outcrops of Convolute Flysch may be visited. This is<br />
a two-component flysch, with rhythms of 10-25 cm<br />
of arenites (limy or marly sandstones, graded bedded,<br />
frequently with convolute laminated bedding at<br />
the upper part) and pelites (marls or silty marls, dark,<br />
grey or green). According to the micropaleontological<br />
and palynological assemblages, this Lower Convolute<br />
Flysch Member is of Lower and partly of Middle<br />
Albian age. In the Bicaz Lake area the Lower Convolute<br />
Flysch constitutes the frontal part of the nappe,<br />
overthrusting the Audia Nappe.<br />
Stop 2.8:<br />
“Black Shales” Formation in the Audia locality.<br />
The Audia locality and brook are situated in the Audia<br />
Nappe outcropping area. The main formation known<br />
in this nappe, developed in the so-called “Silesian<br />
Lithofacies”, is the “Black Shales” Formation of Barremian-Albian<br />
age (according to the palynological<br />
assemblages and the ammonitic faunas). This Formation<br />
may be divided into three sequences: Member<br />
with pelosiderites (lower), Shaly Member (middle)<br />
and Quartzitic Sandstones with glauconite Member<br />
(upper). The specific lithology is represented by black<br />
or dark-grey clays and silty clays. Different inlayerings<br />
make the difference between the different members:<br />
calcareous sandstones and sideritic limestones<br />
(pelosiderites) in the lower member, black jaspers<br />
(lyddites) in the middle and largely developed graded<br />
bedded quartzitic sandstones in the upper one. The<br />
sandstones also contain lithic fragments of Dobrogean<br />
type “Green Schists”, which is proof that the source<br />
area of the arenites is situated within the Foreland<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
(actually underthrust – Figure - below the nappes of<br />
the Flysch Zone). The “Silesian Lithofacies” is also<br />
known in the more external nappes (Tarcău and Marginal<br />
Folds) and represents the outer development of<br />
the Flysch Zone sedimentary basin. It was sedimented<br />
in euxinic conditions, the dark shales having a relatively<br />
high content of bituminous material.<br />
A few hundred of meters downstream from Stop<br />
2.8 the field-trip penetrates into the Tarcău Nappe<br />
outcropping area. The Hangu Formation (see Stop<br />
1.4) crops out in numerous points. 700-800 m before<br />
reaching the Bicaz Dam the “Black Shales” Formation<br />
crops out in the core of the Cârnu Anticline, a<br />
structure of the Tarcău Nappe.<br />
Stop 2.9:<br />
Tarcău Sandstone at the Bicaz Dam. The Bicaz<br />
Dam is built on massive Tarcău Sandstone. The latter<br />
can be examined near the western margin of the<br />
dam. It is a typical sandy flysch with two-components<br />
(quartzose-micaferous, with rare lithic fragments,<br />
arenites and clayey lutites) rhythms of 30-120 cm..<br />
The age of the Tarcău Sandstone (total thickness of<br />
about 3-4 km) is Upper Paleocene-Middle Eocene<br />
(Lutetian), according to the micropaleontological<br />
data (agglutinated foraminiferas assemblages); at the<br />
Bicaz Dam the uppermost level of the Tarcău Sandstone<br />
(with Cyclammina amplectens and Sphaerammina<br />
subgaleata) crops out also showing red clay<br />
intercalations. The Tarcău Sandstone is followed by<br />
a two-component flysch (limy sandstones / marls and<br />
clays) with rhythms of 10-25 cm of Upper Eocene age<br />
– the Podu Secu Formation – with inlayerings of<br />
Globigerina Marls (see also stop 1.3) at the terminal<br />
levels. The “Shaly Horizon” of the lower part of the<br />
Oligocene and the Fusaru Sandstone (see Stop1.5)<br />
follows.<br />
From the Bicaz Dam the field-trip reaches the town<br />
of Bicaz and from there it turns westward along the<br />
Bicaz Valley. It will cross the whole inner part of the<br />
Flysch Zone in reverse sense (Audia, Convolute Flysch,<br />
Ceahlău nappes) as the field-trip crossed them in<br />
the Bistriţa Valley.<br />
Stop 2.10:<br />
The front of the Bucovinian Nappe at the locality<br />
of Bicazul Ardelean .<br />
On the right-hand bank of the Bicaz River, at the confluence<br />
with the Dămuc Brook in the western part of<br />
Bicazul Ardelean, the front of the Bucovinian Nappe<br />
as well as a tectonic (“rabotage”) outlier carried from<br />
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the Subbucovinian sedimentary envelope, are well<br />
exposed (Săndulescu, 1975).<br />
In the S u b b u c o v i n i a n o u t l i e r the following lithostratigraphic<br />
succession can be examined : Anisian<br />
dolomites representing the main part of the outlier/<br />
Lower Jurassic (?) coarsegrained quartzites/Middle<br />
Jurassic sandy limestones with Trocholina div.sp.,<br />
Bositra buchi,Zeilleria div.sp., Parkinsona parkinsoni<br />
etc. Discordantly, thin bedded Tithonian limestones/<br />
limy polymictic breccias with inlayerings of marly<br />
limestones. Along the frontal part of the Bucovinian<br />
nappe such “Rabotage” Outliers crop out frequently<br />
(cf. Stop 2.1 too). Another lithostratigraphical succession<br />
with respect to the Gura Dămucului shows:<br />
Callovian-Oxfordian radiolarites, Tithonian-Neocomian<br />
pelagic limestones, with breccias inlayerings<br />
in the Neocomian. This two types of successions<br />
proceed from different parts of the Subbucovunian<br />
domain, with different paleogeographic evolutions. A<br />
third type of Subbucovinian lithostratigraphy may be<br />
considered the Putna Valley succession (Stop 1.10).<br />
The F r o n t a l p a r t of the Bucovinian Nappe is represented<br />
by metamorphic formations of the Tulgheș Series<br />
(sericitic-quartzitic and sericitic-graphitic schists<br />
with inlayerings of metabasalts and porphyroids).<br />
Stop 2.11:<br />
The External Limb of the Hăghimaș Syncline :<br />
At 1,5 km west from the Bucovinian front, upstream<br />
along the Bicaz Valley, the massive Anisian dolomites<br />
mark the outer limb of the Hăghimaș Syncline.<br />
Lower Triassic quartzitic sandstones discontinously<br />
develop at their base. A pre-Barremian or even - taking<br />
into account the general structure of the outer limb<br />
of the syncline – pre-Late Jurassic imbrication may<br />
be demonstrated on the left-hand bank of the Bicaz<br />
where a scale involving Middle Jurassic rocks may<br />
be examined. With an angular discordance, the Wildflysch<br />
Formation follows, with a similar lithologiy to<br />
that of the Rarău Syncline (see Stop 1.7).<br />
The Wildflysch Formation is tectonicaly overlapped<br />
by the outliers of the Hăghimaș Transylvanian Nappe<br />
(the big limestones quarries upstream from Stop<br />
2.11). Both Wildflysch Formation and Transylvanian<br />
Nappe are transgressively covered by the Bârnadu<br />
Conglomerates (Vraconian ? – Cenomanian) which<br />
constitute the Post-Tectogenetic Cover. The conglomerates<br />
crop out along the road 2 km upstream from<br />
the quarries. The Hăghimaș Transylvanian Nappe can<br />
be examined in the Bicaz Gorges (Cheile Bicazului)<br />
upstream until the eastern margin of the touristic lo-<br />
cality of Lacu Roșu.<br />
Stop 2.12:<br />
Bicaz Gorges (confluence with the Bicăjel Brook).<br />
In the area of the confluence between the Bicaz with<br />
the Bicăjel the Tithonian-Neocomian succession<br />
of the Hăghimaș Nappe is exposed (Săndulescu,<br />
1975). The Tithonian is represented by massive<br />
light coloured neritic limestones which contain<br />
gastropods (Nerinea), foraminiferas (Trocholina<br />
alpina, T.elongata, Kurnubia, Kilianina, etc.), calcareous<br />
algae (Salpingoporella anulata) as well as<br />
Elipsactinia, Cladocoropsis mirabilis, Clypeina<br />
div.sp., Actinoporella podolica etc. The Berriasian<br />
is represented by well layered pelagic limestones<br />
with Calpionella elliptica, Tintinopsella carpathica,<br />
Calpionellopsis oblonga, Neocomites neocomiensis,<br />
Berriassiella privasensis. The Neocomian has a similar<br />
lithology (massive neritic limestones) and follows<br />
clearly above the Berriasian formations. Downstream<br />
from the confluence (about 600 m ), the Neocomian<br />
limestones are covered, with a slight discordance,<br />
by Urgonian-type ones (white, yellowish and light<br />
reddish limestones and calcarenitic breccias which<br />
contain Pachyodonts [Requienia div.sp. Toucasia<br />
carinata], large foraminiferas [Orbitolina conica] as<br />
well as calcareous algae and briozoarians; the age of<br />
these limestones is at least Lower Barremian, possibly<br />
Barremian as a whole but not younger because they<br />
are inbedded as sedimentary klippen in ([Upper Barremian<br />
??] Aptian formations of the Wildflysch).<br />
Stop 2.13:<br />
“Cheile Bicazului” Tectonic Half - Window.<br />
On the left-hand (northern) slope of the Bicaz River<br />
around the Chalet “Cheile Bicazului” (Bicaz Gorges)<br />
erosion has exposed a tectonic half-window from<br />
which the Wildflysch Formation crops out below the<br />
Hăghimaș Nappe. At the base of the latter, bodies of<br />
mafic and ultramafic rocks emplaced (Săndulescu<br />
and Russo-Săndulescu, 1981). Along the left-hand<br />
bank of the Bicaz River the following succession<br />
may be examined: above the Wildflysch, pillow-lava<br />
basalts and amygdaloid basalts, overlapped by siltic<br />
siliceous shales and red marls (Kimmeridgian), representing<br />
the first sedimentary levels above the Middle<br />
Jurassic oceanic crust. The succession continues with<br />
the massive Tithonian limestones. On the left-hand<br />
slope of the Bicaz River, 300 m behind the Chalet<br />
at the base of the Hăghimaș Nappe are transported<br />
serpentinites which also proceed from the obducted
oceanic crust emplaced at the base of the Transylvanian<br />
nappes.<br />
From the Chalet “Cheile Bicazului” the fieldtrip<br />
continues upstream. After 2 km crossing the massive<br />
Tithonian limestones the road arrives at the inner<br />
erosional contour of the Hăghimaș Nappe and enters<br />
the inner limb of the Hăghimaș Syncline. There the<br />
Mesozoic sequence of the Bucovinian Nappe crops<br />
out largely.<br />
Stop 2.14:<br />
Lacu Roșu - Bucovinian Middle Jurassic-Triassic<br />
formations.<br />
Along the northern bank of the Lacu Roșu (Red<br />
Lake), a lake generated in 1837 by a natural dam<br />
formed by a huge landslide of the right-hand slope<br />
of the Bicaz Valley, the following geological section<br />
(upside/downside) may be examined: sandy limestones<br />
(several hundred meters) with massive layering<br />
(Aalenian-Bajocian) / oolithic-hematitic silty<br />
limestones (50-200 cm) containing condensed fauna<br />
of Sinemurian-Carixian age / rauhwacke dolomites<br />
and limestones (20-70 m) with calcareous algae<br />
(Upper Anisian-Lower Ladinian) / massive Anisian<br />
dolomites.<br />
In the filling of an inward overturned syncline, situated<br />
westward in respect to the previously analysed sequence,<br />
above the Middle Jurassic sandy limestones,<br />
well layered radiolarites of Callovian-Oxfordian age<br />
are exposed.<br />
Stop 2.15:<br />
Hăghimaș Granitoids.<br />
Below the Anisian dolomites or the Lower Triassic<br />
quartzitic sandstones and/or conglomerates of the<br />
inner limb of the Hăghimaș Syncline, the basement<br />
of the sedimentary formations consists of compact<br />
red augengneisses, with fine intercalations of biotitemuscovite<br />
paragneisses. Their general attitude is N<br />
50-67 W/55 NE. The red gneisses consist of quartz<br />
(35%), orthoclase (49%), oligoclase (11%) and biotite<br />
(5%). A gradual transition can be seen from red<br />
orthogneisses to gray granular gneisses, which also<br />
carry garnet. The augengneisses are interpreted as<br />
laminated granitoids.The Hăghimaș Granitoids are<br />
a part of the Bretila Series which is overthrust above<br />
the Tulgheș Series, during the Paleozoic (a Caledonian<br />
or a Hercynian tectonic event). This overthrust,<br />
corresponding to the Rarău Nappe, is a structure of<br />
the metamorphic basement of the Bucovinian Nappe<br />
and was not involved in the Mesozoic tectogeneses<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
(N. Stan, 2000).<br />
The fieldtrip reaches the Pângăraţi Pass (1257m) situated<br />
on the main East Carpathian crest, separating the<br />
Transylvanian hydrographic basins from the Moldavian<br />
ones. From the Pângăraţi Pass a panoramic view<br />
of the Volcanic Chain and the Gheorgheni Quaternary<br />
Depression opens westwards. Eastwards the Mesozoic<br />
Hăghimaș Syncline with the Hăghimaș Nappe<br />
in the axial part shows its panoramic view. From<br />
the Pângăraţi Pass downstream along Belcina Brook<br />
(left-hand tributary of the Mureș River) the metamorphic<br />
formations of the Tulgheș Series of the Bucovinian<br />
Nappe are crossed. Below it the Negrișoara Series,<br />
belonging also to the Bucovinian Nappe metamorphic<br />
basement crops out in several points. The Pietrosu<br />
Gneisses (cropping out 4 – 4.7 km east of Gheorgheni),<br />
a schistose gneiss with relict phenoclasts of violaceous<br />
quartz can be examined. From Gheorgheni<br />
the fieldtrip turns toward south proceeding to Miercurea<br />
Ciuc. After crossing the Gheorgheni or Ciucul de<br />
Sus (Upper Ciuc) Quaternary Depression, situated<br />
between the Volcanic Chain (west) and the Crystalline-Mesozoic<br />
Zone (east), 11 km from Gheorgheni in<br />
the village of Voșlabeni, the median part of the Rebra<br />
Series crops out.<br />
Stop 2.16:<br />
Voșlăbeni Quarry – Rebra Series<br />
(middle sequence).<br />
The Rebra Series is the lowermost series known in<br />
the metamorphic basement of the Bucovinian Nappe.<br />
The same position is recorded in the Subbucovinian<br />
Nappe. The Rebra Series is divided into three Formations.<br />
The middle one – named in this area the<br />
Voșlăbeni Formation – consists of dolomitic marbles<br />
with tremolite and talc, exposed in the Voșlăbeni<br />
quarry. From Voșlăbeni to Miercurea Ciuc metamorphic<br />
formations (mainly Rebra Series) of the Bucovinian<br />
Nappe will be crossed as well as the Ciucul de<br />
Mijloc (Middle Ciuc) Quaternary Depression.<br />
DAY 3<br />
Miercurea Ciuc - Brașov - Sibiu<br />
A i m s : In the Brașov and Perșani Mts. it is possible to<br />
approach the problems concerning the correlation of<br />
the East and South Carpathians.<br />
From Miercurea Ciuc the fieldtrip proceeds southwards,<br />
downstream along the Olt Valley. In the<br />
suburbs of the town, on the left-hand slope of the<br />
valley small quarries are opened in lava flows of py-<br />
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roxene- and hornblende-andesites of Upper Pliocene<br />
? – Lower Pleistocene age, which belong to the calcalkaline<br />
volcanic arc of the East Carpathians. After<br />
crossing the Ciucul de Jos (Lower Ciuc) Quaternary<br />
Depression, the Olt River (and the fieldtrip) crosses<br />
the south-east end of the volcanic chain. At Tușnad<br />
spa, east of the valley, the Sfânta Ana volcanic structure<br />
is well preserved. It is a very young volcano of<br />
Pleistocene or even Holocene age. Downstream, in<br />
the Micfalău area, on the right-hand slope of the Olt<br />
Valley, two subvolcanic bodies of basaltoid andesites<br />
(Lower Pleistocene) are exposed in two large quarries.<br />
On the left-hand slope and tributaries, Lower<br />
Cretaceous flysch formations of the Ceahlău Nappe<br />
are developed. At Malnaș the tectonic contact between<br />
the Ciuc Digitation and the Bodoc Digitation<br />
(both sub-units of the Ceahlău Nappe) is crossed.<br />
From Ghidfalău the Olt River runs within the Sfântu<br />
Gheorghe Quaternary Depression, filled - as the<br />
whole complex developed Quaternary depressions of<br />
the inner part of the Carpathian Bend Area - with Upper<br />
Pliocene-Pleistocene formations.<br />
Between Hărman and Brașov, south of the Depression,<br />
it is possible to reconstruct (if the weather is<br />
favourable), along the skyline, a cross-section of the<br />
Ceahlău Nappe and the front of the Getic Nappe.<br />
Stop 3.1:<br />
Săcele - Jurassic formations in the front of the<br />
Getic Nappe.<br />
In the town of Săcele, the main part of Bonloc Hill<br />
is built up of Jurassic formations similar to those of<br />
the whole Postăvaru Mts.-Codlea-Piatra Craiului<br />
Mts. area, which belong to the Getic Nappe. After<br />
a few siltic black shales of the Grestner Lithofacies<br />
of the Lower Jurassic, Middle Jurassic quartzitic<br />
sandstones follow, hosting a sill of trachytes, also<br />
of Middle Jurassic age. The Upper Jurassic is represented<br />
by massive neritic limestones. The absence of<br />
the Callovian-Oxfordian radiolarites which are usually<br />
developed in the other parts of the Getic Domain,<br />
accentuates the existence of a stratigraphic gap in the<br />
frontal part of the Getic Nappe.<br />
The Săcele Jurassic Getic formations are overthrust<br />
above the Piscu cu Brazi Formation (see Stop 2.4)<br />
of the Ceahlău Nappe.<br />
Brașov is one of the main towns of Transylvania. It is<br />
an early medieval city with many important vestiges.<br />
The Black Church is a famous Catholic church built<br />
in the XV th century in Gothic style. The building<br />
material consists of limy sandstones, which were<br />
worked out from quarries around Teliu village (east<br />
of Brașov) and are massive sandstones intercalated in<br />
the Piscu cu Brazi Formation of the Ceahlău Nappe.<br />
The organ of the church is one of the biggest organs<br />
in the Catholic or Protestant churches in Transylvania.<br />
Council Square is the old centre of the burg, with a<br />
city museum. South of the Black Church, upstream, is<br />
the Orthodox Saint Nicholas Church, where the first<br />
Romanian printing occurred.<br />
Stop 3.2:<br />
Brașov – Ladinian limestones in Dealul Melcilor<br />
Quarry.<br />
Dealul Melcilor Hill is the northern end of Tâmpa<br />
Hill, not far from the centre of town. On its eastern<br />
slope Ladinian organogenous massive limestones<br />
are exposed in an old quarry. They constitute the core<br />
of an E-W oriented anticline belonging to the Getic<br />
Nappe. Above the Ladinian limestones the Gresten<br />
Lithofacies of the Lower Jurassic follows (black siltic<br />
shales dominate with intercalations of quartzitic sandstones);<br />
a sill of arfvedsonite granite porphyry is intruded<br />
in a black siltic sequence. The Middle Jurassic<br />
is represented by quartzitic sandstones, while the<br />
Kimmeridgian-Tithonian by the massive Stramberg<br />
limestones. Tâmpa Hill consists of these limestones<br />
as does the north slope of the Dealul Melcilor.<br />
From Brașov the fieldtrip proceeds to the village of<br />
Cristian (6 km toward south-west) situated in the<br />
western foothills of the Postăvaru Mts.<br />
Stop 3.3:<br />
Cristian – Anisian limestones (Guttenstein type).<br />
North of Râșnov, at the southern margin of the village<br />
of Cristian in an old quarry, well layered limestones<br />
crop out, blackish or dark-grey, slightly bituminous<br />
(“stinking”), frequently with diaclases. Their Anisian<br />
age is documented by ammonitic fauna and by the<br />
palynological assemblages. The Guttenstein-type Triassic<br />
was folded before the Lower Jurassic; Grestentype<br />
formations overlie the Triassic formations with<br />
angular discordance .<br />
The Anisian limestones of Guttenstein type, of the<br />
Cristian-Vulcan area, may be correlated with the Anisian<br />
dolomites and limestones of the Iacobeni quarry<br />
(Stop 1.12). Consequently it is possible to correlate<br />
the Getic Nappe (to which the Cristian section belongs)<br />
with the Infrabucovinian nappes of the Central<br />
East Carpathians.
Stop 3.4:<br />
Râșnov – Upper Jurassic limestones.<br />
About 7 km south of the Cristian quarry, in the center<br />
of Râșnov, massive neritic Stramberg-type Kimmeridgian-Tithonian<br />
limestones crop out in a clifflike<br />
hill. The specific feature of the Cetăţii Brook<br />
outcrop (at Râșnov) consists of a changed lithofacies<br />
of the lower part of the carbonate sequence (welllayered<br />
limestones, probably Kimmeridgian-Lower<br />
Tithonian. Such situations are scarce, but emphasize<br />
that in some areas sedimentation starts with basinal<br />
lithofacies, synchronous with the massive neritic one,<br />
passing upwards to neritic, generalized lithofacies.<br />
On the top of the limestone relief, in the XIV th century<br />
, a peasant fortress was built, which is one of the several<br />
defence fortresses built around Brașov.<br />
From Râșnov the fieldtrip returns to Cristian and from<br />
there proceeds west crossing the Bârsa Plain (which<br />
corresponds to the Bârsa Quaternary Depression)<br />
until Vulcan .<br />
Stop 3.5:<br />
Vulcan – Anisian / Spathian boundary.<br />
At the western margin of the village of Vulcan, 250 m<br />
from the Vulcan-Holbav road, in a small old quarry,<br />
limy shales and thin black limestones, weakly bituminous<br />
crop out. With a thickness of 10-30 m, they<br />
develop at the base of the Guttenstein-type Anisian<br />
limestones. From the stratigraphical point of view<br />
they are situated at the boundary between the Middle<br />
Triassic (Anisian) and the Lower Triassic (Spathian).<br />
From Vulcan village the fieldtrip follows a local road<br />
until Holbav village and west of it.<br />
Stop 3.6:<br />
Dealul Merezi (Merezi Hill) – metamorphics of the<br />
Voinești Formation.<br />
In several small outcrops, on the western slope of<br />
Dealul Merezi in the eastern suburb of Holbav,<br />
feldspathic quartzites and retrogressed micaceous<br />
paragneisses are exposed. They belong to the Voinești<br />
Formation of the Leaota Group.<br />
Stop 3.7:<br />
Holbav – Lower Jurassic in Gresten Lithofacies.<br />
130 m upstream on the Bisericii Brook, in Holbav,<br />
in several mining, the rocks which constitute the<br />
Gresten lithofacies developed in the Holbav area may<br />
be examined: quartzitic sandstones, coarse-grained<br />
sandstones with quartzitic grains and coal-bearing<br />
siltic matrix, coal-bearing clays or clayey silts,<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
sideritic limestones. In the middle part of the Gresten<br />
lithofacies, in the Holbav area, alkaline rocks (alkalibasalts,<br />
trachytes, camptonites, bostonites) are inlayered<br />
as lava-flows or sills. This volcano-sedimentary<br />
formation is a specific feature of the Holbav Gresten<br />
Lower Jurassic and is absent in the other zones where<br />
the Gresten Lithofacies is known (Cristian, Brașov,<br />
Săcele).<br />
Stop 3.8:<br />
Holbav Gneiss west of Holbav.<br />
150 -200 m downstream from the westernmost houses<br />
of Holbav, large outcrops of the Holbav Gneisses may<br />
be examined. They consist of augengneisses with centimetric<br />
pink or white augen of K-feldspar, interpreted<br />
either as migmatites or as orthogneisses derived from<br />
porphyric granites.<br />
The Holbav Gneiss is overthrust above the Lower<br />
Jurassic. This overthrust coresponds to the frontal<br />
part of the Supragetic nappes, the Șinca Nappe respectively.<br />
Northward the frontal overthrust of the<br />
Supragetic nappes can be followed, in outcrop, until<br />
the Dealu Mare Fault (easternmost segment of the<br />
South Transylvanian Fault) (Figure1). The Supragetic<br />
nappes correspond, in the Central East Carpathian<br />
area (Crystalline-Mesozoic Zone) to the Subbucovinian<br />
and the Bucovinian nappes.<br />
The fieldtrip returns to Vulcan and from there continues<br />
northwards to Codlea. The Măgura Codlei Scale<br />
is well expressed in the relief. It is constituted mostly<br />
of Upper Jurassic massive neritic limestones (Stramberg-type),<br />
which preserve at their base Callovian -<br />
Oxfordian radiolarites and Middle Jurassic calcareous<br />
sandstones. The Măgura Codlei Scale is thrust in front<br />
of the Subbucovinian (Șinca) Nappe.<br />
From Codlea, where a medieval fortified church<br />
marks the center of the locality, the fieldtrip turns<br />
west, entering the Vlădeni Couloir. This is well<br />
expressed in the flat and lower relief. The southern<br />
margin of the Vlădeni Couloir is represented by the<br />
Dealu Mare Fault (see above). This fault is marked<br />
by a sharp morphology corresponding to the elevation<br />
of the southern border of the Couloir, which is<br />
in fact a half-graben, tilted at its southern part. The<br />
Vlădeni Couloir filling consists of Upper Cretaceous<br />
conglomerates and coarsegrained sandstones and of<br />
marls (Senonian), thin and discontinous developed<br />
Eocene formations (sandstones and marls) and Oligocene-Lower<br />
Miocene dominantly marly lithofacies,<br />
slighty bituminous.<br />
Near Perșani village the south-east border of the<br />
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Transylvanian Depression is crossed by the national<br />
road which is followed by the fieldtrip. In some quarries<br />
on the slope, north of the road, the Dej Tuff crops<br />
out. It is a general marker of the basal sequence of the<br />
Depression clearly followed in boreholes and on the<br />
seismic lines.<br />
Stop 3.9:<br />
Panoramic view of the innermost part of the<br />
Carpathian Bend Area.<br />
From Șercaia village it is possible to have a panoramic<br />
view of the Perșani Mts., the Vlădeni Couloir,<br />
the Dealu Mare (South Transilvanian) Fault and the<br />
north-eastern end of the Făgăraș Mts. The highest<br />
visible relief of the Perșani Mts. corresponds to a<br />
large domal anticline (Gârbova Anticline) in the core<br />
of which metamorphic formations of the Bucovinian<br />
Nappe crop out. On the north-western slope (left-hand<br />
slope of Gârbova Mts.) the whole sedimentary succession<br />
of the nappe develops. The south-eastern slope is<br />
overlain by the Upper Cretaceous post-tectogenetic<br />
cover of the Bucovinian Nappe. It corresponds to the<br />
northern limb of the Vlădeni Depression. The Dealu<br />
Mare Fault is well expressed in relief (see above). The<br />
Făgăraș Mts., with the beautiful panorama of their<br />
skyline, correspond - with a small exception - to the<br />
Subbucovinian Nappe. On a small area at Șinca Nouă<br />
and Vârful lui Petru (the latter visible as the highest<br />
peak on the skyline), a tectonic outlier of the Bucovinian<br />
Nappe is preserved.<br />
From Șercaia to Sibiu the fieldtrip runs across the<br />
southernmost part of the Transylvanian Depression.<br />
Southward (left-hand) the Făgăraș Mts. border the<br />
Depression. Northward the hills are built up of Sarmatian<br />
and, mostly, Pannonian formations.<br />
Sibiu is also an important medieval town. The<br />
Evangelic Cathedral was built in the oldest part of<br />
the town, where the medieval architecture was well<br />
preserved. Parts of the defence works of the XV th -<br />
XVI th centuries are also well preserved. The Ortodox<br />
Cathedral was the first one built in Transylvania,<br />
showing an architecture similar to that of Saint Sophia<br />
in Constantinople. The Brukenthal Museum* is the<br />
oldest painting exhibition, opened one year before<br />
the Louvre.<br />
DAY 4<br />
Sibiu - Alba Iulia - Câmpeni<br />
From Sibiu to Alba Iulia the fieldtrip runs along the<br />
southern border of the Transylvanian Depression. Af-<br />
ter crossing Alba Iulia, the fieldtrip enters the Ampoi<br />
Valley.<br />
Stop 4.1:<br />
Șard - Miocene molasse.<br />
The oldest formations belonging to the Transylvanian<br />
Depression, cropping out in the Alba Iulia area, are<br />
exposed in Șard, on the right-hand bank of Ampoi<br />
Brook. Conglomerates, microconglomerates and<br />
coarsegrained sandstones of red or grey colour may<br />
be examined. The pebbles and grains are of different<br />
types, proceeding from the Miocene erosion of the<br />
South Apuseni Mountains.This molassic formation<br />
is older than the Dej Tuff (Lower Badenian). Consequently<br />
they may be correlated with the Hida Formation<br />
which is of uppermost Burdigalian/lowermost<br />
Badenian age.<br />
After Șard, along the Ampoi Valley the fieldtrip runs<br />
across the Feneș Unit of the South Apuseni Mts.<br />
(Transylvanides).<br />
Stop 4.2:<br />
Ampoi Valley - the Meteș Formation.<br />
The Upper Aptian -Albian sequence of the Feneș<br />
Nappe is represented by the Meteș Formation. This<br />
is a typical wildflysch formation, the sedimentary<br />
klippen (“olistoliths”) being represented by ophiolitic<br />
and sedimentary rocks which proceed from the inner<br />
(southern and eastern) units (Techerău-Drocea and<br />
its prolongation east of the Brad Depression, or the<br />
Trascău Nappe).<br />
The outcrops of the Meteș Formation show a layered<br />
(turbiditic) or massive siltic matrix and sedimentary<br />
klippen of: basalts, calc-alkaline rocks, Oxfordian, Tithonian<br />
and/or Urgonian (Barremian-Lower Aptian)<br />
limestones.<br />
The road continues across the same Meteș Formation,<br />
the landscape dominated by characteristic “Klippen”<br />
of Upper Jurassic limestone olistoliths. Between<br />
Poiana Ampoiului and Presaca Ampoiului, the area is<br />
built up by the Fenes Formation, but the favourable<br />
exposures are situated on the left (northern) affluents<br />
and slopes.<br />
At Presaca Ampoiului, after crossing a fault, the road<br />
enters the Valea lui Paul Formation in which some<br />
Upper Jurassic olistoliths can be observed (Bleahu<br />
et al., 1981).<br />
Stop 4.3:<br />
Feneș valley. Very low-grade Feneș beds.<br />
Along the Feneș valley siltic clayș chemolitic lime-
stones, greywackes, spilites, are exposed; they are<br />
very slightly metamorphosed. This formation is<br />
considered (Bleahu et al., 1981) volcano-sedimentary-olistostrome,<br />
with sequences of turbiditic rocks.<br />
The age of the Feneș Formation is probably Tithonian-Barremian.<br />
Stop 4.4:<br />
Petringeni. Faţa Băii conglomerates and volcanites<br />
(Paleocene).<br />
The molasse deposits of the post-tectonic Paleogene-Miocene<br />
Zlatna basin, transgressive on the<br />
Cretaceous Flysch are represented by the Faţa Băii<br />
conglomeratic Formation. The polymictic conglomerates<br />
admit intercalations of sandstones, red clays,<br />
as well as interlayered lavas and volcaniclastics of<br />
rhyolitic and andesitic composition. The rhyolitic<br />
flows, sometimes brecciated, consist of plagioclase,<br />
sanidine, quartz and biotite. The andesites are amphibole-and<br />
pyroxene-bearing. The thickness of the<br />
lava flows does not exceed 50 m. Paleocene age was<br />
confirmed radiometrically and biostratigraphically.<br />
Westwards the age of the sedimentary and volcanic<br />
formations extends well into the Miocene (E. Roșu in<br />
Udubașa, 2001 ed.).<br />
At Zlatna, at the crossroad to Almăș, Senonian formations<br />
are exposed in a small quarry, consisting of<br />
sandstones, microconglomerates and conglomerates<br />
with pebbles of quartz and limestones.<br />
Upstream from Izvorul Ampoiului the valley crosses<br />
the tectonic contact between the Feneș Nappe and the<br />
Bucium Unit, the latter being represented by the Upper<br />
Albian Pârâul Izvorului Formation (coarse convolute<br />
sandstones, marls and clays).<br />
The road traverses the watershed between the Ampoi<br />
and Arieș basins at Dealul Florii.<br />
Stop 4.5:<br />
Confluence Abrud valley - Cerbu valley.<br />
Soharu Formation (Upper Aptian-Lower Albian).<br />
An overturned Wildflysch sequence of the Bucium<br />
Unit can be examined in a small quarry. The sequence<br />
consists of grey-greenish convolute shales alternating<br />
in the higher levels with calcarenites and calcirudites.<br />
Conglomerates with calcareous cobbles and green<br />
tuffaceous-clayey matrix are also exposed, as well as<br />
greenish or violaceous siltites (S. Bordea, 1992).<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
DAY 5<br />
Câmpeni - Petru Groza - Brad - Deva<br />
Stop 5.1:<br />
Vadu Moţilor. Contact between Lupșa<br />
and Gârda Nappes.<br />
After Paleozoic marbles exploited in a quarry and<br />
a rather monotonous sequence of either sericitic<br />
or chloritic schists, for several kilometers, at Vadu<br />
Moţilor, south of the confluence with the Neagra valley,<br />
at the base of the Muncel Nappe, chlorite-sericite<br />
schists with an intercalation of tuffogeneous amphibolites<br />
are exposed, dipping 35°SE.<br />
North of the confluence, silvery-violaceous laminated<br />
conglomerates crop out with strongly flattened pebbles,<br />
the schistosity dipping southwards. Their age is<br />
Upper Carboniferous-Lower Permian; the conglomerates<br />
belong to the Finiș -Gârda Nappe, the basement<br />
of which consists of the Codru Granitoids, exposed<br />
upstream (Bleahu et al., 1981).<br />
Further on, the road runs across the Codru Granitoids<br />
and migmatites of the Gârda Nappe, as well as across<br />
violaceous quartzitic sandstones and conglomerates<br />
belonging to the Bihor Unit, the basement of which<br />
consists of retrogressed chlorite-sericite schists<br />
(Arada Series). The contact between the two units is<br />
a vertical fault.<br />
Stop 5.2:<br />
Albac Gorge. Skythian-Anisian boundary<br />
in the Bihor Unit.<br />
At the confluence with a small left-hand tributary<br />
decimetric beds of Skythian violaceous or white<br />
quartzitic sandstones are conformably overlain by<br />
Anisian yellowish-white bedded dolomites. The<br />
abrupt contact suggests a break in sedimentation<br />
(Bleahu et al., 1981).<br />
Stop 5.3:<br />
Zugăi Gorge, Bihor Unit. Detrital formation<br />
at the base of the Ladinian.<br />
After crossing for a longer distance massive, brittle<br />
yellowish-white Anisian dolomites, a detritic formation<br />
is exposed along the road for about 100 m, its<br />
sequence being as follows: dolomitic breccia with<br />
clasts of black dolomites; white limestone breccia<br />
with rounded pebbles of Wetterstein limestones and<br />
of Anisian black limestones (regionally unknown in<br />
outcrops); violaceous argillaceous or marly shales,<br />
appearing yellow or grey when weathered, with interbeds<br />
of violet quartzitic sandstones.<br />
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The top of the sequence consists of massive greyishwhite<br />
Wetterstein limestones.<br />
The detritic formation presented above gives evidence<br />
of a continental environment deposition, the<br />
limestone pebbles and the violet clays possibly representing<br />
a karst infilling.<br />
Some hundreds of meters upriver, the Wetterstein<br />
limestones overthrust by Codru Granitoids and<br />
migmatites of the Gârda Nappe are transformed into<br />
calcite mylonites (Bleahu et al., 1981).<br />
Stop 5.4:<br />
Scărișoara - Gârda. Upper Carboniferous-Lower<br />
Permian of the Gârda Nappe.<br />
After crossing laminated Codru granitoids and migmatites<br />
and a horst exposing Wetterstein limestones in<br />
a half-window, the road reaches the first sedimentary<br />
term of the Gârda Nappe, namely the Laminated Conglomerates,<br />
the Upper Carboniferous-Lower Permian<br />
age of which was evidenced by palynology. They consist<br />
of flattened, mainly quartz pebbles in a violaceous<br />
slaty matrix. An oblique foliation may sometimes be<br />
obseved. Upsequence follows laminated violet or<br />
green rhyolitic ignimbrites and violet shales with<br />
interbeds of red micaceous sandstones (with hyeroglyphs)<br />
(Bleahu et al., 1981).<br />
Measurement of the pebbles has shown that the strain<br />
was predominantly an extensional one, but in places<br />
the main deformation was flattening (Dimitrescu,<br />
1995).<br />
Stop 5.5:<br />
Gârda de Sus - confluence with Iarba Rea. Lower<br />
Permian of the Gârda Nappe.<br />
After crossing again, due to the Gârda major fault,<br />
the Anisian dolomites of the Bihor Unit, the road<br />
continues across the formations of the Gârda Nappe,<br />
the place of the Laminated Conglomerates being<br />
taken by a breccia consisting of fragments reaching<br />
20 cm in length of gneisses, muscovite, schists quartz<br />
and quartzites included in a shaly matrix. They are<br />
believed to be an alluvial deposit, without fluvial<br />
transport and present a striking similarity to the “Conglomerati<br />
di Dosso dei Galli” of the Southern Alps<br />
and with the Medódoly (Kopersady) breccias of the<br />
Tatrides (Bleahu et al., 1981).<br />
Stop 5.6:<br />
Confluence with the Buciniș valley. Arieșeni Nappe<br />
overthrusting the Gârda Nappe.<br />
After crossing a spectacular gorge cut across a syn-<br />
cline of Skythian violaceous quartz conglomerates<br />
and sandstones overlying the Permian micaceous or<br />
feldspathic sandstones and shales, at the confluence<br />
with the Buciniș valley the contact between the Gârda<br />
and the Arieșeni Nappes is exposed. The former is<br />
represented by laminated conglomerates, sandstones<br />
and rhyolites, while the latter consists of green phyllitic<br />
schists of Lower Carboniferous age, the attitude<br />
of their schistosity being about EW with southern dip<br />
(Bleahu et al., 1981).<br />
Stop 5.7:<br />
Arieșeni. Greenschist Formation<br />
(Upper Carboniferous).<br />
From the front of the Arieșeni Nappe overthrust examined<br />
at the previous stop, the road crosses exclusively<br />
the Lower Carboniferous greenschists of this<br />
unit. The large outcrops reveal the schistosity of the<br />
Arieșeni Formation showing various dips, generally<br />
towards W and NW.<br />
At km 40 + 350 m of main road nr. 75, in an exposure<br />
about 10 m long on the left side of the Arieșul Mare,<br />
a subhorizontal exposure may be observed consisting<br />
of weakly metamorphosed conglomerates with<br />
strongly rolled pebbles, composed predominantly of<br />
quartz and with greyish-green quartzitic matrix; the<br />
metaconglomerates admit an intercalation of greyish-green<br />
sandstone and overlie green pelitic schists<br />
cropping out just at the water level. The alternation<br />
of the lithological horizons expresses the S 0 bedding<br />
of the rocks, on the planes of which no foliation has<br />
developed; the attitude of the graphically determined<br />
bedding is approximately N 45° W / 12° SW. Directly<br />
measurable foliation planes correspond to a schistisity<br />
S 1 (flow cleavage) oblique with respect to the bedding;<br />
its attitude here is N 70°W / 45°SW. Along this<br />
foliation small faultings of the lithologic horizons occur<br />
locally. The intersection lineation trends N 67°W<br />
/ 04°NW.<br />
The regional trend of the stretching lineations, marked<br />
by the elongation of the pebbles in the Greenschist<br />
Conglomerates of the Arieșeni Nappe, is NW, signalling<br />
the direction of Alpine tectonic transport in the<br />
Northern Apuseni (Dimitrescu, 1995).<br />
Stop 5.8:<br />
Arieșeni. General view of the Biharia Massif.<br />
The whole crest of the Biharia Massif is built up of<br />
the formations of the Biharia Nappe consisting of the<br />
Biharia crystalline series. It overlies horizontally the<br />
Poiana Nappe made up of a narrow strip of metacon-
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Figure 8 - General cross-section in the Bihor Mts<br />
(M.Bleahu in Ianovici et al., 1976)<br />
I Bihor Unit: SA, Arada Series; ws, Seisian; wcan,Campilian-Anisian;<br />
ld,Ladinian; J1, 2, 3 , Jurassic;<br />
br, Barremian. II Arieș eni Nappe: P, Permian;<br />
T1,Werfenian; III Poiana Nappe: SP, Păiușeni Series;<br />
IV Biharia Nappe: SB, Biharia Series; SP, Păiușeni<br />
Series. V Muncel Nappe: SM, Muncel Series; g,<br />
granitoids.<br />
Southern Apusenides: b, ophiolites; br, Barremian;<br />
st-cp, Santonian, Campanian; ma, Maastrichtian.Posttectogenetic<br />
formations: gd, granodiorites; a, andesites;<br />
gdp, granodiorite porphyry.<br />
glomerates and sericite-phyllites (Upper Carboniferous-Păiușeni<br />
Series). The Poiana Nappe overlies the<br />
Arieșeni Nappe, which covers the whole area lying at<br />
the foot of the Biharia Massif; this nappe consists of<br />
the Arieseni Greenschists Formation and the reddishviolet<br />
formations of the Upper Carboniferous-Lower<br />
and Middle Permian.<br />
In front of and under the Biharia (Cucurbăta)<br />
MicăPeak, a lower peak covered by wood, rises. It<br />
is the Stânișoara Peak, which consists of banatitic<br />
granodiorites piercing the whole pile of Permian<br />
formations. The intrusion determined a contact metamorphism<br />
changing in large areas the red colour of<br />
the Permian into black (“Black Series”) (Bleahu et<br />
al., 1981).<br />
Stop 5.9:<br />
Arieșeni. Unconformity Upper/Lower<br />
Carboniferous.<br />
After leaving the centre of Arieșeni, at km 36 + 550 m,<br />
after the confluence with the Șteului valley, in a large<br />
exposure the unconformity between the Laminated<br />
Conglomerates (Carboniferous-Lower Permian) and<br />
the Arieșeni Greenschists (Lower Carboniferous) may<br />
be examined. In this exposure the pelitic greenschists<br />
are overlain by laminated conglomerates containing<br />
as pebbles weakly rolled quartz fragments included in<br />
a violaceous-silvery sericitic matrix; the conglomerates<br />
alternate with schistose quartzitic sandstones and<br />
argillaceous violet phyllites.<br />
The attitude of the common schistosity S 1 of both<br />
formations is N 40°W / 35°SW. The S 0 bedding of the<br />
greenschists, graphically plotted according to a slight<br />
banding is N 40°E / 38°NW, the trend of the intersection<br />
lineation being EW / 30°W.<br />
The attitude of the bedding of the laminated conglomerates<br />
cannot be observed here. However 200 m upriver,<br />
this attitude put in evidence by pebble grading<br />
and by shaly interbeds is NS / 60°W (trend of inter-<br />
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section lineation: N53°E/ 36°SW). The regional trend<br />
of the stretching lineations marked by the elongation<br />
of the pebbles in the Laminated Conglomerates of the<br />
Arieșeni Nappe is also north-western, confirming the<br />
direction of the Alpine tectonic transport.<br />
The strain of the pebbles was exclusively an extensional<br />
one, as measurement of their shape has shown,<br />
the intensity of deformation being medium.<br />
Comparing the Es parameters for the pebbles of the<br />
Greenschist conglomerates with those of the Laminated<br />
Conglomerates in the Arieșeni Nappe, it may<br />
be concluded that the former were more intensely<br />
deformed (Es = 0.55 - 1.22 versus 0.55 - 0.80), having<br />
undergone an older Midcarboniferous tectonic phase<br />
that did not affect the latter. On Flinn’s diagram, the<br />
majority of the pebbles shows a k~1, the strain having<br />
been a plane one in the Laminated Conglomerates of<br />
the Arieșeni Nappe (Dimitrescu, 1995).<br />
Stop 5.10:<br />
Bubești Hill. Permian Vermicular<br />
Formation. Banatitic sill.<br />
At km 32 + 120 m, on the left slope of the valley<br />
above the road, the Permian is represented by red<br />
micaceous sandstones and argillaceous shales. In the<br />
sandstones, bioglyphs of burrow - fillings type can<br />
be observed. The Permian is pierced by a banatitic<br />
andesite sill.<br />
Stop 5.11:<br />
Piatra Muncelului. Lamprophyre dykes crossing<br />
Urgonian limestones.<br />
After reaching the main watershed of the Apuseni<br />
Mountains, the road leaves the Arieș hydrographic<br />
basin and enters the Crișul Negru basin, intersecting<br />
reddish Permian and quartzitic Lower Triassic<br />
formations.<br />
After a number of road windings and hair-pin bends<br />
across Lower Jurassic detrital formations changed<br />
into hornfelses (“Black Series”), a fault is traversed<br />
and then white massive limestones of Barremian in<br />
Urgonian facies belonging to the lowermost Bihor<br />
Unit are continuously exposed.<br />
At km 21 + 50 m, three almost vertical lamprophyre<br />
dykes striking about NS are intruded into the limestones.<br />
The thickness of the dykes ranges between<br />
1 and 3 m; the eastern one presents at its contact a<br />
breccia about 1 m thick, composed of angular fragments<br />
of white limestones (recrystallized as marbles)<br />
and of igneous rocks, enclosed in a calcareous-gritty<br />
cement.<br />
The lamprophyres correspond to odinites, consisting<br />
of basic plagioclase and augite, the ground-mass<br />
having an intergranular texture. It is worth noting the<br />
presence of pyroxenes as phenocrysts (Bleahu et al.,<br />
1981).<br />
Stop 5.12:<br />
Arieșeni - Băiţa road. Contacts Arieșeni<br />
Nappe / Următ Nappe / Bihor Unit.<br />
In the last outcrops of the limestones (km 20 + 60 m)<br />
numerous Coral traces as well as remnants of Megalodonts<br />
are to be observed; then, at the road surveyor’s<br />
cabin, the road crosses from the Bihor Unit into the<br />
Următ Nappe. The latter consists of slight micaceous<br />
shales, yellowish quartz sandstones and greyish calcarenites,<br />
all of them assigned to the Lower Jurassic.<br />
Further on, the road leads again into the Arieșeni<br />
Nappe consisting mainly of the Permian violaceous<br />
rocks. Red coloured rocks are gradually replaced<br />
by black coloured ones (“Black Series”) due to the<br />
thermal action of the banatitic body intruded here at a<br />
small depth (Bleahu et al., 1981).<br />
Stop 5.13:<br />
Băiţa Bihorului. Rhyolites in the black Permian.<br />
On entering the old mining locality of Băiţa Bihorului,<br />
opposite the first houses, on the right slope, a<br />
rhyolitic body is exposed. Its colour is light grey, due<br />
to thermal metamorphism with very slight violaceous<br />
hues at places. The rock presents a feebly pronounced<br />
foliation; the attitude of the layering is approximately<br />
N 20°E / 40°SE; two main joint systems are observable.<br />
The footwall consists of blackish vermicular<br />
micaceous sandstones, while in the hanging wall, the<br />
contact with black argillites and quartzites may be<br />
observed (“Black Series”).<br />
Past the town of Băiţa, on the right-hand side, the formation<br />
of the Bătrânescu Nappe appear contacting the<br />
Arieșeni Nappe along a fault. Skythian quartzites followed<br />
by dolomites and limestones of Middle Triassic<br />
age can be noticed. Finally the road reaches the Beiuș<br />
Depression with outcrops of Pliocene.<br />
Stop 5.14:<br />
Vașcău. Permian ignimbritic rhyolites.<br />
Ignimbritic rhyolites are exposed about 400 m west of<br />
the Vașcău railway station. White feldspar and quartz<br />
crystals about 1-3 mm in size are conspicuous, as well<br />
as leafy biotite, included in a greenish-grey schistose<br />
matrix. Characteristic “fiamme” are often noticed in<br />
the latter (N. Stan in Borcoș et al., 1980).
Stop 5.15:<br />
Dealul Mare. Metaconglomerates of the<br />
Păiușeni Series.<br />
The road crosses the divide between the hydrographic<br />
basins of the Black and the White Criș; at this point,<br />
the metaconglomerates of the Poiana Nappe are exposed.<br />
Measurements on their pebbles indicated an extensional<br />
strain for the whole Poiana Nappe, in one point<br />
only the strain is a flattening one.<br />
The road continues across the Miocene post-tectonic<br />
basin.<br />
Between Brad and Vălișoara upriver the Luncoiu valley<br />
on both sides of the main road, Mesozoic islandarc<br />
(U3-K1) andesitic-basaltic volcanics (basalts and<br />
andesites are associated with gabbros, but also with<br />
dacites, rhyolites as well as with orthophyres and oligophyres<br />
as pyroclastics) as well as the Miocene molasse<br />
deposits represented mainly by the red “Almasu<br />
Mare gravels” (Badenian) are exposed; the latter belong<br />
to the Brad-Săcărâmb sedimentary basin where<br />
the Neogene volcanics are widely developed.<br />
In the Dealul Mare col the characteristic landscape of<br />
volcanic peaks is to be seen.<br />
At Vălișoara, the Upper Jurassic andesitic and basaltic<br />
flows and pyroclastics are overlain by Upper<br />
Jurassic calcareous olistoliths and by Aptian Wildflysch<br />
formations.<br />
Downstream the Vălișoara valley, after the island-arc<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Figure 9 - Simplifi ed map of Vâlcan-Parâng Mts.<br />
(T.Berza and V.Iancu, 1994).<br />
complex beginning at Săliștioara the road crosses<br />
ophiolitic rocks belonging to the Techerău Nappe,<br />
porphyritic basaltic lavas with augite phenocrysts,<br />
andesites with hornblende as well as porphyroclastics<br />
(aglomerates and tuffs) are conspicuous (Savu et al.,<br />
1986).<br />
Some “Klippen” of Upper Jurassic and Urgonian<br />
limestones can be noticed.<br />
Succeeding the ophiolitic complex, after an EW striking<br />
fault, the Căbești Formation (Barremian-Lower<br />
Aptian) is exposed, namely black gritty shales with<br />
intercalations of siliceous sandstones; they belong to a<br />
particular unit, the Căbești Unit (Bleahu et al., 1981).<br />
Stop 5.16:<br />
Fornădia. Mesocretaceous unconformity.<br />
A small hill marks the unconformity between the<br />
Căbești Formation, represented by strongly disturbed<br />
quartzitic sandstones and clayey shales and the gently<br />
dipping Fornădia Beds (Vraconian-Cenomanian).<br />
The latter start with quartzitic micro-conglomerates<br />
and calclithites. The coarse bedding becomes thinner<br />
(15-50 cm) towards the top of the formation. In thin<br />
slides Paraphillum primaevum is frequent.<br />
After another EW oriented fault, the road reaches<br />
the area of the Bejan Unit, in which the Bejan Formation<br />
is characteristic. This formation consists of<br />
B12<br />
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Volume n° 1 - from PR01 to B15<br />
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Leader: M. Sandulescu<br />
black argillaceous shales with olistoliths of Jurassic<br />
basalts, Upper Triassic and Upper Jurassic micritic<br />
limestones, interbedded with basaltic flows, pyroclastics<br />
and epiclastics and sandstones, representing<br />
an olistostrome.<br />
Along the Mureș valley, again after an EW trending<br />
fault, outcrops of the Deva Formation can be examined.<br />
The conglomerates, massive sandstones and<br />
marls are of Coniacian-Santonian age, constrained by<br />
micropaleontological data (Bleahu et al., 1981).<br />
The fieldtrip reaches Deva, a town dominated by a hill<br />
built up by a Neogene amphibole andesite (+ biotite<br />
volcanic neck) with a ruined fortress of the XV th century<br />
on its top.<br />
DAY 6<br />
Deva - Tg.Jiu - Turnu Severin<br />
From Deva, the fieldtrip reaches Hunedoara, a town<br />
famous in the country not only for its metallurgical<br />
plants but also for the beautiful castle, built in the<br />
middle of the XV th century. Its foundations rest on<br />
a cliff of Lower Carboniferous crystalline dolomites<br />
belonging to the Supragetic Units of Poiana Ruscă.<br />
Underlying the dolomites, low-grade iron deposits<br />
were mined representing the basis for the local metallurgical<br />
industry.<br />
From Hunedoara, the road crosses the Neogene Strei<br />
basin.<br />
Stop 6.1:<br />
Crivadia Bridge. Getic Nappe: Lotru basement<br />
and Mesozoic cover.<br />
Between Crivadia and Băniţa, national road 66<br />
crosses the Getic (Austrian) Nappe represented by the<br />
Lotru Group basement and the Lower Jurassic-Lower<br />
Cretaceous cover. Aalenian-Bathonian sandstones<br />
and bioclastic limestones are followed by bioclastic<br />
limestones with siliceous deposits (Lower-Middle<br />
Callovian) and Upper Jurassic-Aptian pelletal and<br />
micritic Urgonian limestones (T. Berza, in: Berza et<br />
al., 1994).<br />
Before entering Petroșani, the Lotru Group is exposed,<br />
consisting of micaschists and micaceous paragneisses<br />
with muscovite, biotite and garnet. They are sometimes<br />
affected by retrogression, by which the primary<br />
minerals are substituted by sericite and chlorite.<br />
The Petroșani Tertiary basin follows, with red Aquitanian<br />
conglomerates and coal-bearing Chattian<br />
sandstones.<br />
Stop 6.2:<br />
Gambrinus Motel. Liassic Schela Formation.<br />
At the confluence of the Eastern and the Western Jiu<br />
(km 125 on national road 66 ), a small road after 150<br />
m leads to the Gambrinus Motel. The Liassic Schela<br />
Formation is exposed along a forest road beginning<br />
immediately before the motel. It consists of black<br />
metapelitic and metapsammitic rocks of Gresten type.<br />
On the southern slope of the Vâlcan Mountains, the<br />
Figure 10 - Schematic cross-section along the Jiu Gorges (Berza, Drăgănescu,in Berza et al.,1994). 1,Tertiary<br />
deposits; 2,Lotru rocks; 3,Upper Cretaceous Flysch with Lupeni limestone klippen;4,Schela Formation;5,Lainici-<br />
Păiuș rocks; 6,Drăgșan amphibolites; 7, Șușiţa Pluton; 8,unconformity; 9, ”decollement”stratigraphic boundary;<br />
10,Alpine overthrust; 11, pre-Alpine overthrust
same formation bears fossil flora.<br />
The dominant attitude of the schistosity in the black<br />
phyllites is N 75°E / 40°SW; it represents an axial<br />
plane foliation of concentric decimetric and metric<br />
folds trending N 22°E / 30°SW (B 1), accompanied<br />
by a faint crenulation lineation with the same attitude.<br />
Younger chevron folds trend N 50°W / 75°SW (B 2).<br />
Along B 1, conspicuous boudins of quartzose material<br />
can be observed, due to contrast in competence;<br />
they indicate a tectonic transport top-to-NE. A parallel<br />
system of short centimetric quartz veins lead to the<br />
same conclusion.<br />
Stop 6.3:<br />
Km 118.500 on national road 66. Amphibolitic<br />
Formation of the Drăgșan Group.<br />
A typical leptyno-amphibolitic formation is exposed,<br />
with an alternation of millimetric to centimetric<br />
black and white layers dipping 45°SE. All proportions<br />
between 100% hornblende and amphibole-free<br />
oligoclase + quartz layers can be found. Biotite,<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
garnet and muscovite are frequent. Scarce layers of<br />
mica-gneisses occur in the amphibolites (T. Berza, in:<br />
Berza et al., 1994).<br />
Stop 6.4:<br />
Cârligul (Cornul) Caprei bridge, km 115.500. Pre<br />
- Alpine tectonic contact between two distinct basements<br />
(Lainici - Păiuș and Drăgșan) of the Lainici<br />
Nappe.<br />
The last outcrops of the Drăgșan Group are fine- to<br />
large-grained massive garnet amphibolites (metagabbros),<br />
preceded by serpentinites (metaperidotites).<br />
Downriver to 100 m north of the bridge, the retrogression<br />
is limited to fracture zones, frequently with<br />
quartz veins. Near the bridge, contrasting mechanical<br />
properties of carbonates and silicates and pervasive<br />
deformation produced black (amphibolite) or white<br />
(leucogranite) boudins in the marbles.<br />
On the following hundreds of meters downriver to<br />
km 114.500, the road exposes para-amphibolites,<br />
mica-gneisses, graphitic metapelites and silicate<br />
Figure 11 - Tectonic sketch-map of the south-western part of the South Carpathians. (Codarcea et al.,1968).<br />
B12<br />
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Volume n° 1 - from PR01 to B15<br />
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Leader: M. Sandulescu<br />
marbles with ubiquitous leucogranite injections;<br />
the entire sequence is strongly sheared, with a steep<br />
foliation and EW - trending horizontal lineation. Manolescu<br />
(1937), Pavelescu et al., (1964) and Berza et<br />
al., (1983) ascribe this carbonatic-graphitic sequence<br />
to the Lainici-Păiuș Group, while Savu et al., (1984)<br />
consider it as part of the Drăgșan Group (T. Berza, in:<br />
Berza et al., 1994).<br />
Stop 6.5:<br />
Km 111. Lainici-Păiuș Group in the<br />
Lainici Nappe.<br />
Downriver to km 106 (Lainici Monastery), the Jiu<br />
Gorges are carved into the Lainici-Păiuș Group,<br />
exposing its Quartzitic Formation (an alternance of<br />
various quartzites, biotite gneisses and mica-gneisses).<br />
Leucogranitic injections and various migmatites<br />
are widespread. The general aspect of the rocks is<br />
mylonitic, with a pervasive north-dipping mylonitic<br />
foliation and retrograde greenschist facies recrystallization.<br />
Several porphyritic dykes are emplaced in this<br />
sequence. Relict mineral assemblages of an early high<br />
T-low P metamorphism (Precambrian) are preserved<br />
in places (andesine, garnet, sillimanite, andalusite,<br />
cordierite, hornblende), strongly overprinted by later<br />
greenschist retrogression (albite, chlorite, tremolite,<br />
epidote, stilpnomelane) (T. Berza, in: Berza et al.,<br />
1994).<br />
Stop 6.6:<br />
Km 105. Rafaila - Lainici-Păiuș gneisses<br />
and Schela Formation.<br />
At the Rafaila Cross, the left bank of the Jiu shows<br />
mostly Quaternary deposits at the mouth of a lefthand<br />
tributary, with huge blocks of sandstones and<br />
conglomerates and smaller debris of pyrophyllitechloritoid<br />
slates (famous occurrence of chloritoid).<br />
The Liassic age is well documented by plant remains<br />
further west. The Schela Formation is overthrust<br />
southwards by the Lainici-Păiuș Formation (Lainici<br />
Nappe). On the next 500 m of the road, rocks of the<br />
Lainici - Păiuș Group are exposed: quartzites ± plagioclase<br />
± biotite ± muscovite ± garnet ± diopside<br />
alternate with mica gneisses ± sillimanite. The latter<br />
may reach 2 cm in length and show a strong horizontal<br />
EW-trending lineation. Dikes of porphyritic microdiorites<br />
show a pervasive Alpine mylonitization.<br />
The first outcrops of Șușiţa granitoids begin at km<br />
103.700, the rocks being foliated and altered, being<br />
transformed into quartz-albite-K feldspar-muscovite-<br />
chlorite-stilpnomelane-epidote mylonites.<br />
Down to the Runc brook, the granitoids have been affected<br />
by a Hercynian schistosity. They are laminated<br />
and transformed into sericite-chlorite “orthoschists”;<br />
the K feldspar megacrysts resist better to the deformation<br />
processes (T. Berza, in: Berza et al., 1994).<br />
Stop 6.7:<br />
Km 97. Șușiţa granitoids.<br />
The Șușiţa pluton consists of biotite granites and<br />
biotite- hornblende granodiorites and tonalites. The<br />
texture is more or less massive. It is the longest pluton<br />
of the South Carpathians (50 km in length).<br />
After leaving the Jiu Gorges the fieldtrip proceeds<br />
across the Neogene formations of the Getic Piedmont.<br />
Stop 6.8:<br />
Tismana monastery. Tismana granite.<br />
The porphyritic coarse-grained Tismana granites consist<br />
of microcline, plagioclase (An 30), quartz, biotite<br />
and accessories. The K-feldspar megacrysts reach<br />
lengths of 10 cm; the plagioclases do not exceed 1<br />
cm. Equigranular granodiorites also crop out in the<br />
vicinity of the hydroelectric adit. A subhorizontal<br />
metric vein of aplitic rocks crosses the granitoids.<br />
Associated in the same magmatic suite meladiorites<br />
are exposed, upriver consisting of clinopyroxene,<br />
brown hornblende, biotite, plagioclase (An 40-50),<br />
interstitial quartz, apatite. The fabric is massive.<br />
Static retrograde mineral alterations include formation<br />
of chlorite, prehnite, epidote.<br />
The Mesozoic cover consists of Liassic conglomerates<br />
and arkosic sandstones (T. Berza, in: Berza et<br />
al., 1994).<br />
The church of the Tismana monastery was built<br />
in the XIV th century; its other buildings date from a<br />
much later period.<br />
Stop 6.9:<br />
Brebina valley at Bratilovu, km 48 along the Baia<br />
de Aramă - Băile Herculane road. Getic Nappe<br />
overlying the Danubian.<br />
Between Brebina and Titerlești, the road crosses the<br />
uppermost term of the Lower Danubian cover, namely<br />
a Upper Cretaceous Wildflysch formation, consisting<br />
of a highly broken sequence of turbidites showing<br />
a block-in-a-sheared matrix texture. The olistoliths<br />
include Mesozoic rocks, basalts, serpentinites and<br />
crystalline schists, while the matrix consists of siltites<br />
and argillaceous shales.<br />
The deformational history includes tectonic shearing
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Figure 12, 13 - Geological map and cross section-Danube Valley between Gura Văii and Orșova (V.Iancu,<br />
Fl.Marinescu, S.Năstăseanu, M.Conovici in Pop et al.,1997).<br />
and gravitational mass transport. Shear-sense indicators<br />
suggest dextral shearing, connected to a major<br />
EW -trending dextral strike-slip fault (8-10 km of<br />
horizontal displacement). (A. Seghedi, in Berza et<br />
al., 1994).<br />
In Bratilovu, the mylonitic rocks with western dips of<br />
the Lotru Group belonging to the Getic Nappe crop<br />
out.<br />
Across the villages of Mărășesti and Stănești, the<br />
road exposes outcrops of crystalline schists of the<br />
Getic Bahna outlier.<br />
Stop 6.10:<br />
Obârșia Cloșani. Km 52-56. Severin Nappe. The<br />
Severin Nappe in this area is represented by the<br />
Obârșia Complex, a melange formation with ophiolites<br />
and siliceous pelagic deposits (radiolarian cherts)<br />
assigned to the Upper Jurassic-Lower Cretaceous.<br />
The ophiolitic rocks are basalts (in places with pillow<br />
texture), dolerites, harzburgitic ultramafites and<br />
minor gabbros, pervasively sheared and disrupted.<br />
Geochemical features suggest MORB -tholeiites. The<br />
rocks preserve fresh pyroxenes. Along the Brebina<br />
valley, spotted basalts show low-temperature meta-<br />
B12<br />
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Leader: M. Sandulescu<br />
morphism in prehnite-pumpellyite facies. Other secondary<br />
minerals of the sheared rocks include chlorite,<br />
epidote, albite, calcite and zeolites. The structural<br />
elements of the ophiolites consist of slickensides and<br />
S-C fabrics, with a penetrative scaly-cleavage. Flat<br />
lying banded mylonites develop on basalt protoliths<br />
along the western border of the nappe. Sheared green<br />
rocks are traversed by epidote-quartz-albite veins (A.<br />
Seghedi, in Berza et al., 1994).<br />
The road continues across Neogene formations till<br />
Drobeta -Turnu Severin. This town was built at the<br />
emplacement of Trajan’s bridge over the Danube (105<br />
A.D.), one pillar of which can still be seen. Medieval<br />
ruins can also be visited.<br />
DAY 7<br />
Turnu Severin - Timișoara<br />
Stop 7.1:<br />
3.5 km west of Gura Văii, km 352, between the<br />
Scarpia (Padina Mică) and Ungureanu viaducts.<br />
Pre-Alpine polymetamorphic basement of the<br />
Getic Nappe: Lotru Group.<br />
The road crosses the Iron Gate outlier of the Getic<br />
Nappe, on which the Iron Gate Dam is built. The<br />
Lotru Group consists of metaterrigeneous micaceous<br />
paragneisses and micaschists associated with<br />
amphibolites, quartz-feldspar gneisses and scarce<br />
marble lenses. The outcrops display up to three fold<br />
generations, S 1 layering, S 2 dominanat transposition<br />
foliation and a S 3 crenulation cleavage, mineral and<br />
intersection lineations.<br />
Relict mineral assemblages (biotite, garnet, staurolite,<br />
kyanite) characterizing a first barrovian metamorphism<br />
M1 are overprinted by a sillimanite + biotite +<br />
muscovite association M2 of intermediate low-pressure<br />
type. The dominant S2 foliation has a general<br />
NE-SW attitude, while the mineral (stretching) lineations<br />
lie between ENE and ESE.<br />
The Iron Gates outlier of the Getic Nappe crosses the<br />
Danube southwards into Serbia (Sip) (V. Iancu, in:<br />
Pop et al., 1997).<br />
Stop 7.2:<br />
Slătinicu Mare viaduct (km 354) and Oreva<br />
viaduct (1.3 km westwards). Tectonic contact at<br />
the sole of the Getic Nappe (Bahna outlier ) with<br />
Lower Cretaceous turbidites (Sinaia Beds) of the<br />
underlying Severin Nappe.<br />
Metamorphites of the previously examined Lotru<br />
Group, with small bodies of sheared diatexitic gran-<br />
ites, overlie the Sinaia Beds, lying in the core of a<br />
large scale open antiformal fold. On the eastern end of<br />
the viaduct, the outcrop consists of crystalline schists<br />
of the Lotru Group, while on its western end the Sinaia<br />
Beds are exposed.<br />
The Sinaia Beds include mostly distal turbidites;<br />
thicker sandstone beds up to 40-50 cm occur in the<br />
vicinity of the Slă˘tinicu Mare viaduct. Grey pelagic<br />
limestones form thin interbeds. Chondritid ichnofauna<br />
is often preserved in siltstones and mudstones. The<br />
age of the sequence is ascribed to the Upper Tithonian-<br />
Lower Valanginian, according to Calpionellids.<br />
The structural style of the Sinaia Beds consists of tight<br />
to isoclinal recumbent folds (B 1) strongly refolded<br />
by steeply dipping normal folds (B 2). The recumbent<br />
folds are strongly disrupted by normal folding and<br />
they are often preserved as isolated dismembered fold<br />
hinges. Various types of kink- and chevron-folds with<br />
axial planes steeply dipping E or W are common.<br />
Slaty cleavages are seldom visible in the pelitic interbeds.<br />
Sandstone beds may show fracture cleavages<br />
fanning in fold hinges. Younger structures are high<br />
angle normal faults.<br />
The relationships between the Lotru Group of the<br />
Getic Nappe and the Sinaia Beds are exposed on<br />
the right-hand bank of the Slătinic valley, where the<br />
metamorphic rocks show pervasive brittle deformation.<br />
The tectonic contact can be followed uphill,<br />
where the metamorphic rocks of the Lotru Group<br />
build up the top of the hills, while the road is cut<br />
across sedimentary deposits. 300 m east of the Oreva<br />
viaduct, strongly sheared and brecciated metamorphites<br />
reappear in the core of a tight synformal fold;<br />
a steeply dipping shear band foliation occurs in both<br />
formations, several meters away from the contact (A.<br />
Seghedi,V. Iancu, in : Berza et al., 1994; Pop et al.,<br />
1997).<br />
Stop 7.3:<br />
Km 357, Vodiţa viaduct - Vârciorova viaduct. Tectonic<br />
contact between the Severin Nappe and the<br />
Danubian Domain.<br />
At the confluence with the Vodiţa valley, the Lotru<br />
Group is exposed.<br />
The oldest sedimentary deposits exposed eastwards<br />
are massive grey limestones strongly jointed and<br />
crossed by numerous calcite veinlets, exhibiting in<br />
places a pseudobreccia aspect. Their age is ascribed<br />
to the Upper Jurassic-Lower Cretaceous, by comparison<br />
with the Cerna-Coșuștea zone. These deposits<br />
represent a huge olistolith embedded into a paratypi-
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Figure 14 - Geological sketch of the Bârzava Valley (Moniom-Bocșa) (Iancu, Năstăseanu in Năstăseanu et al., 1981).<br />
1, Quaternary; 2, Neogene; 3, Banatitic magmatites.Locva Unit:4, Upper Carboniferous and Lower Cretaceous; 5,<br />
Lower Carboniferous(Cârșie Formation); 6, Devonian, volcano-sedimentary formation:a, metapelites; b, metatuffs<br />
and metatuffites; 7, metamorphoseded igneous rocks; 8, Ordovician(?), Tâlva Mare Quartzites;Bocșa Unit: 9,<br />
Upper Carboniferous and Middle Jurassic-Lower Cretaceous; 10, Precambrian-Lower Cambrian,Bocșiţa-Drimoxa<br />
Formation; 11, Precambrian,Tâlva Drenii Formation. Reșiţa Nappe:12, Upper Carboniferous.<br />
cal Wildflysch Lower Senonian Formation consisting<br />
of red and green marls, black shales and of a sequence<br />
known as Vârciorova Sandstone. The latter consists of<br />
massive calcareous sandstones, grading up to stratified<br />
sandstones, with interbeds of conglomerates and<br />
microconglomerates, including unsorted lithoclasts of<br />
gneisses, quartzites, micaschists and limestones.<br />
Trace fossils occur within the pelitic terms, mainly<br />
Chondritids. The major constituents of the sandstones<br />
are plagioclase and quartz; detrital micas are muscovite<br />
and partly chloritised biotite. The carbonate cement<br />
is micritic to largely recrystallized.<br />
Walking eastwards the overlying Severin Nappe<br />
(known in Serbia as the Kosovica Nappe) consists<br />
of Azuga Beds = Kasajna Beds in Serbia (red and<br />
green shales, displaying sometimes a phyllitic aspect;<br />
red radiolaritic cherts, manganese cherts, sandy calcarenites<br />
and sandstones), their age being ascribed to<br />
the Upper Jurassic, and by the previously examined<br />
Sinaia Beds.<br />
The overthrust plane of the Severin nappe is marked<br />
by mylonites. Before the construction of the new<br />
road, the lower part of the nappe contained small<br />
exposures of ophiolites.<br />
A comparable succesion was described by Grubic´<br />
(1992) in the Dzevrin hill in Serbia, south of the<br />
Danube.<br />
A vertical fault separates the Danubian from the<br />
Bahna outlier of the Getic Nappe, the latter being<br />
prolonged south of the Danube into Serbia (Tekija).<br />
Orșova is built upon a Miocene basin (V. Iancu, A.<br />
Seghedi, in: Pop et al., 1997).<br />
Stop 7.4:<br />
Bela Reka valley. Mehadia. Lower Lias.<br />
At the southern entrance into Mehadia, on the lefthand<br />
bank of the Bela Reka river, the Lower Lias is<br />
exposed. It overlies transgressively the Permian, represented<br />
by red conglomerates with argillitic matrix;<br />
in the dominating Străjiuţul hill, Permian eruptive<br />
rocks crop out. The Lower Lias consists of an alternance<br />
of conglomerate banks, quartzitic breccia and<br />
sandstones, grey or blackish, with black gritty shales<br />
as intercalations (Codarcea et al., 1961).<br />
B12<br />
41 - B12<br />
Volume n° 1 - from PR01 to B15
Volume n° 1 - from PR01 to B15<br />
B12<br />
B12 -<br />
Leader: M. Sandulescu<br />
Stop 7.5:<br />
Bela Reka valley. Middle Lias.<br />
Upstream the Bela Reka valley, black shales with<br />
gritty intercalations of the Middle Lias crop out,<br />
characteristic for the Gresten facies. Their age is constrained<br />
by faunas with Ostrea cymbium, Belemnites<br />
paxillosus, Pholadomya sturi. Upwards they grade<br />
into the Upper Lias, with Posidonia bronni (Codarcea<br />
et al., 1961).<br />
Stop 7.6:<br />
Timiș valley between Teregova and Sadova Veche.<br />
Armeniș Formation of the Lotru Series.<br />
The lowermost term of the Lotru Series consists of<br />
nodular sillimanite-bearing biotite gneisses, pearlgneisses,<br />
quartz-feldspar gneisses, amphibolites and<br />
amphibole-gneisses, marbles and calc-silicate rocks<br />
(Savu, 1970; Săbău, 1994). Pegmatite veins are frequent.<br />
The top of the formation is represented by the<br />
thin Piatra Scrisă amphibolite level, overlain by almandine,<br />
kyanite and staurolite bearing micagneisses<br />
and schists (Săbău, 1994).<br />
Stop 7.7:<br />
Moniom. Relations between the Getic Reșiţa<br />
Nappe and the Supragetic Moniom Nappe.<br />
Leaving Moniom, the (Westphalian C.) Doman Beds<br />
of the Reșiţa Nappe will be crossed up to the Cârșie<br />
Hill, where they are overthrust by the metamorphic<br />
rocks of the Moniom Nappe along the Oraviţa tectonic<br />
line. The uppermost term of the Reșiţa Nappe is<br />
represented by the Carboniferous Cârșie Formation.<br />
It consists of metaconglomerates, metasandstones and<br />
phyllites. In the former, the pebbles decrease in size<br />
westwards. The stretching lineations are materialized<br />
by the N30 - 40°E / 10 -30°NE trending elongations<br />
of the pebbles. Analysis of the finite strain put in<br />
evidence its high intensity (Rf > 2,5) and its plane<br />
character. The Oraviţa tectonic line represents a post-<br />
Supragetic Nappe dextral transcurrent fault, inducing<br />
a simple shear in the Carboniferous formations (M.<br />
Dimitrescu, 2000).<br />
Westwards along the Bârzava river, the Devonian<br />
Valea Satului Formation of the Moniom Nappe consists<br />
of chlorite-epidote-actinolite-albite schists (±<br />
quartz, sericite, calcite) representing mylonitic basic<br />
metatuffs, metatuffites and metaaglomerates, with<br />
intercalations of carbonatic and graphitic rocks, acid<br />
metatuffs also being present, as well as metagabbroic<br />
intrusions.<br />
The described formations exhibit subhorizontal ini-<br />
tial stratification surfaces (S 0 ) and almost vertical S 2<br />
cleavages.<br />
The Valea Satului Formation was parallelized with<br />
the Leșcoviţa “Series” exposed along the Danube (V.<br />
Iancu, in: Năstăseanu et al., 1981).<br />
Stop 7.8:<br />
Colţan tunnel. Bocșa Nappe overthrust onto the<br />
Moniom Nappe.<br />
Along the Bârzava valley, above the Colţan railway<br />
tunnel, the Valea Satului Formation of the Moniom<br />
Nappe is overthrust by the Bocșiţa-Drimoxa Formation<br />
of the Bocșa Nappe. The latter formation consists<br />
of muscovite-chlorite-albite plagiogneisses, with biotite<br />
and garnet relics ( mainly enclosed in plagioclase<br />
porphyroblasts); it crops out about 200 m west of the<br />
forest chalet. The rocks exhibit intrafolial transposition<br />
folds, the limbs of which are cut by a S2 foliation<br />
with a westward dip. Westwards, the plagiogneisses<br />
alternate with rare microcline augengneisses and<br />
orthoamphibolites (V. Iancu, in: Năstăseanu et al.,<br />
1981).<br />
The Mesozoic cover of the basement formations is<br />
represented by marbles, the age of which is ascribed<br />
to the Middle-Upper Jurassic-Lower Cretaceous.<br />
The Bocșiţa-Drimoxa Formation was parallelized<br />
with the Locva “Series” exposed along the Danube<br />
(V. Iancu).<br />
Stop 7.9:<br />
Bârzava valley - Bocșa Nouă. Banatitic massif.<br />
The contact zone between the Bocșa banatitic pluton<br />
and the intruded Supragetic augen-and plagiogneisses<br />
is exposed. A first intrusion of micromonzodiorite<br />
porphyry is penetrated by a granodiorite, carrying<br />
xenoliths of both crystalline schists and eruptive<br />
rocks. The micromonzodiorite porphyry of the early<br />
magmatic stage (Western Unit) contains large hornblende<br />
and biotite phenocrysts. The monzogranites<br />
and granodiorites Medium Unit consists of zoned<br />
plagioclase (20-35 % An), microcline, quartz, biotite<br />
and hornblende (Russo-Săndulescu et al., 1975; in<br />
Năstăseanu et al., 1981).<br />
The respective K - Ar ages of the succesive intrusions<br />
are 87 m.y. (B 1) and 80 - 81 m.y. (B2) that is, intra<br />
- Senonian.<br />
Acknowledgements<br />
The authors would like to express their gratitude to<br />
Dr. Mihaela Dimitrescu, Miss Elena Negulescu and<br />
Miss Delia-Georgeta Dumitraș (Geological Institute
of Romania) for carefully editing the manuscript and<br />
figures of this guide.<br />
Thanks are due to the Geological Institute of Romania,<br />
Bucharest, for the facilities generously put at our<br />
disposal.<br />
The authors acknowledge with thanks a Grant from<br />
the Romanian Academy (Nr. 94 / 2003) which enabled<br />
them to carry out the elaboration of this guide.<br />
References cited<br />
I Field-<strong>Guidebook</strong>s<br />
Balintoni, I., Berza, T., Hann, H., Iancu,V., Kräutner,<br />
H.,Udubașa, G. (1989). Precambrian Metamorphics<br />
in the South Carpathians. 71 p. Bucharest.<br />
Berza, T., Iancu, V., Seghedi, A., Nicolae, I., Balintoni,<br />
I.,Ciulavu, D., Bertotti, G. (1994). ALCAPA II.<br />
Excursion to South Carpathians, Apuseni Mountains<br />
and Transylvania Basin: Description of stops. Rom.<br />
Journ.Tect.Reg.Geol.75, suppl. 2, 105-149. Bucharest.<br />
Bleahu, M., Lupu, M., Patrulius, D., Bordea, S.,<br />
Ștefan, A., Panin, S. (1981). The Structure of the<br />
Apuseni Mountains. CBGA XII CONGR., B3, 108<br />
p. Bucharest.<br />
Borcoș, M., Peltz, S., Stan, N., Berbeleac, I. (1980).<br />
Neogene and Permian volcanism in the Apuseni<br />
Mountains and the East Carpathians.136 p. Inst.<br />
Geol., București.<br />
Cioflica, G., Savu, H., Nicolae, I., Lupu, M., Vlad, S.<br />
(1981). Alpine Ophiolitic Complexes in South Carpathians<br />
and South Apuseni Mountains. CBGA XII<br />
CONGR., A3, 80 p. Bucharest.<br />
Codarcea, Al., Bercia, I., Boldur, C., Constantinof, D.,<br />
Maier, O., Marinescu, Fl., Mercus, D., Năstăseanu, S.<br />
(1968). Geological structure of the Southwestern Carpathians.<br />
XXIII Intern. Geol. Congr. (Prague), Exc.<br />
49 A C, 50 p. Bucharest.<br />
Kräutner, H., Năstăseanu, S., Berza, T., Stănoiu, I.,<br />
Iancu, V. (1981). Metamorphosed Palaeozoic in the<br />
South Carpathians and its relations with the pre-Palaeozoic<br />
Basement. CBGA XII CONGR., A 1, 116 p.<br />
Bucharest.<br />
Năstăseanu, S., Bercia, I., Iancu, V., Vlad, S., Hârtopanu,<br />
I. (1981). The Structure of the South Carpathi-<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
ans (Mehedinţi-Banat Area). CBGA XII CONGR., B<br />
2, 100 p. Bucharest.<br />
Nedelcu, L., Hârtopanu, P., Szakacs, Al., Moga, C.,<br />
Podașcă, I. IV Nat. Symp. Mineralogy (Iași), Field<br />
Trip. Rom. Journ. Mineralogy, 78, suppl. 2, 40 p.<br />
Bucharest.<br />
Pop, Gr., Mărunţiu, M., Iancu, V., Seghedi, A., Berza,<br />
T. (1997). Geology of the South Carpathians in the<br />
Danube Gorges (Romanian Bank). 28 p. Bucharest.<br />
Săndulescu, M., Ștefănescu, M., Butac, A., Pătruţ,<br />
I., Zaharescu, P. (1981 a). Genetical and Structural<br />
Relations between Flysch and Molasse (The East<br />
Carpathians Model). CBGA XII CONGR., A 5, 96<br />
p. Bucharest.<br />
Săndulescu, M., Kräutner, H., Balintoni, I., Russo-<br />
Săndulescu, D., Micu, M. (1981 b). The Structure of<br />
the East Carpathians (Moldavia-Maramureș Area).<br />
CBGA XII CONGR., B 1, 92 p. Bucharest.<br />
Săndulescu, M., Borcoș, M., Bordea, S., Dimitrescu,<br />
R., Ștefan, A. (1992). Les Carpates.Tectonique de<br />
Compression-Subduction-Magmatisme Connexe.<br />
Réun.extraord. SGF en Roumanie. Guide, 43 p. Bucarest.<br />
Udubașa, G. (ed.) (2001). Geodynamics and Ore<br />
Deposit Evolution of the Alpine-Balkan-Carpathian-<br />
Dinaride Province. Rom. Journ. Min. Dep. 79, suppl.<br />
2, 6-13. Bucharest.<br />
II Geological maps of the Geological Institute of<br />
Romania<br />
East Carpathians<br />
1:50000<br />
Bercia, I., Bercia , E., Săndulescu, M., Szasz, L.<br />
(1975). Sheet Vatra Dornei.<br />
Kräutner, H., Kräutner, Fl., Săndulescu, M., Bercia,<br />
I., Bercia, E., Alexandrescu, Gr., Ștefănescu, M., Ion,<br />
J. (1975). Sheet Pojorâta.<br />
Mureșan, M., Peltz, S., Seghedi, I., Szakacs, Al., Bandrabur,<br />
T., Kräutner, H., Săndulescu, M., Mureșan,<br />
G., Peltz, M., Kräutner, Fl. (1986). Sheet Voșlăbeni.<br />
Săndulescu, M., Bandrabur, T., Mureșan, M., Vasilescu,<br />
Al. (1971). Sheet Miercurea Ciuc.<br />
B12<br />
43 - B12<br />
Volume n° 1 - from PR01 to B15
Volume n° 1 - from PR01 to B15<br />
B12<br />
B12 -<br />
Leader: M. Sandulescu<br />
Săndulescu, M., Patrulius, D., Ștefănescu, M. (1972).<br />
Sheet Brașov.<br />
Săndulescu, M., Bandrabur, T,Vasilescu, Al., Peltz, S.<br />
(1973). Sheet Sânmartin.<br />
Săndulescu, M., Mureșan, M., Mureșan, G. (1975).<br />
Sheet Dămuc.<br />
Săndulescu, M., Micu, M., Alexandrescu, Gr., Constantin,<br />
P. (1987). Sheet Câmpulung Moldovenesc.<br />
1:200000<br />
Alexandrescu, Gr., Mureșan, G., Săndulescu, M.<br />
(1968). Sheet Topliţa.<br />
Joja, T., Alexandrescu, Gr., Bercia, I., Mutihac, V.,<br />
Dimian, M. (1968). Sheet Rădăuţi.<br />
Săndulescu, M., Vasilescu, Al., Popescu, A., Mureșan,<br />
M., Arghir-Drăgulescu, A., Bandrabur, T. (1968).<br />
Sheet Odorhei.<br />
Apuseni Mountains<br />
1:50000<br />
Borcoș, M., Berbeleac, I., Bordea, S., Bordea, J.,<br />
Mantea, G., Boștinescu, S. (1981). Sheet Zlatna.<br />
Bordea, S. and Borcoș, M. (1972). Sheet Brad.<br />
Bordea, S., Ștefan, A., Borcoș, M. (1979). Sheet<br />
Abrud.<br />
Bordea, S.,Dimitrescu, R., Mantea, G., Ștefan, A.,<br />
Bordea, J., Bleahu, M., Costea, C. (1989). Sheet<br />
Biharia.<br />
Dimitrescu, R., Bordea, J., Bordea, S. (1974). Sheet<br />
Câmpeni.<br />
Dimitrescu, R.,Bleahu, M., Lupu, M. (1977). Sheet<br />
Avram Iancu.<br />
Lupu, M., Kräutner, H., T¸icleanu, M., Boștinescu, S.,<br />
Bandrabur, T., Kräutner, Fl., Horvath, A., Nicolae, I.<br />
(1982). Sheet Deva.<br />
1:200000<br />
Lupu, M., Borcoș, M., Dimian, M., Lupu, D., Dimitrescu,<br />
R. (1967). Sheet Turda.<br />
South Carpathians<br />
1:50000<br />
Bercia, I., Bercia, E., Năstăseanu, S., Berza, T., Iancu,<br />
V., Stănoiu, I., Hârtopanu, I. (1977). Sheet Obârșia<br />
Cloșani.<br />
Berza, T., Seghedi, A., Pop, Gr., Szasz, L., Hârtopanu,<br />
I., Săbău, G., Moisescu, V., Popescu, Gh. (1986).<br />
Sheet Lupeni.<br />
Ghenea, C., Russo-Săndulescu, D., Iancu, V., Ghenea,<br />
A., Rogge-T¸ăranu, E. (1984). Sheet Berzovia.<br />
Hârtopanu, I., Stan, N., Iancu,V., Năstăseanu, S., Hârtopanu,<br />
P., Marinescu, Fl., Dinică, I., Bercia, I., Tatu,<br />
M., Săbău, G. (1987). Sheet Orșova.<br />
Năstăseanu, S., Iancu, V., Savu, H., Russo-<br />
Săndulescu, D. (1985). Sheet Reșiţa.<br />
Pop, Gr., Berza, T., Marinescu, Fl., Stănoiu, I., Hârtopanu,<br />
I. (1975). Sheet Tismana.<br />
Savu, H., Stan, N., Năstăseanu ,S., Marinescu, Fl.,<br />
Stănoiu, I. (1984). Sheet Schela.<br />
Săndulescu, M., Popescu, G., Săndulescu, J., Mihăilă,<br />
N., Schuster, A. (1972). Sheet Zărnești.<br />
1:200000<br />
Năstăseanu, S., Bercia ,I., Bercia, E., Biţoianu, C.<br />
(1968). Sheet Baia de Aramă.<br />
Năstăseanu, S., Stancu, J., Ilie, S. (1968). Sheet<br />
Reșiţa.<br />
Savu, H., Ghenea, C., Ghenea, A. (1966). Sheet Turnu<br />
Severin.<br />
Savu, H., Pavelescu, M., Stancu, J., Lupu, D. (1968).<br />
Sheet Orăștie.<br />
III References cited<br />
General Structure and Evolution of the Romanian<br />
Carpathians<br />
Săndulescu, M. (1980). Analyse géotectonique des<br />
chaines alpines situées autour de la Mer Noire occidentale.<br />
An. Inst. Geol. Geofiz. LVI, București.<br />
Săndulescu, M. (1984). Geotectonica României. Ed.<br />
Tehnică, București.<br />
Săndulescu, M. (1994). Overview on Roumanian<br />
Geology. In: “ ALCAPA II “, Rom. J. Tect. Reg. Geol.,<br />
75, suppl. 2, Bucharest.<br />
Geological Structure of the East Carpathians<br />
Antonescu, E. (1975). L’Anisien de Cristian. In: “ 14 th<br />
European Micropal. Coll.” (Micropal. Guide. Mesoz.<br />
and Tertiary Rom. Carpath.), Inst. Geol. Geofiz.,
București.<br />
Antonescu, E., Ion, J., Alexandrescu, Gr. (1978).<br />
Nouvelles données biostratigraphiques concernant<br />
les Schistes Noirs et les Argiles Bariolés des Carpates<br />
Orientales. D. S. Inst. Geol. Geofiz. LIV / 4,<br />
București.<br />
Antonescu, E. and Săndulescu, M. (1985). Quelques<br />
données palynologiques concernant la Nappe du<br />
Flysch Courbicortical de la vallée du Trotuș (Carpathes<br />
Orientales). D. S. Inst. Geol. Geofiz. LXIX /<br />
4, București.<br />
Antonescu, E., Bratu, E., Ion, J., Ionescu, A., Micu,<br />
M., Săndulescu, M. (1989). Biostratigraphy of the<br />
Paleogene Flysch formations of the Roumanian Carpathians.<br />
14 th Congr. CBGA, Extended Abstr., Sofia.<br />
Balintoni, I. (1985). Contributions to the knowledge<br />
of the metamorphic history of the Argestru Series<br />
rocks in the Puciosu brook (East Carpathians). D. S.<br />
Inst. Geol. 69 / 1, 247 - 255, București.<br />
Balintoni, I. (1997). Geotectonica terenurilor metamorfice<br />
din România. Ed. Carpatica, 1-176, Cluj.<br />
Ion - Săndulescu, J. (1975). Microbiostratigraphie,<br />
associations et zones ? foraminifères du Crétacé du<br />
flysch externe des Carpathes Orientales (Roumanie).<br />
Rev. Espan. Micropaleont., Madrid.<br />
Ion, J. (1978). Microbiostratigraphie des dépôts<br />
crétacés de la Nappe du Flysch Courbicortical. Ann.<br />
Soc. Géol. Pol. XLVIII / 2, Krakow.<br />
Ionesi, L. (1971). Flișul Paleogen din bazinul văii<br />
Moldova (French abstr.). Ed. Acad. R. S. România,<br />
București.<br />
Kräutner, H. G. (1980). Lithostratigraphic Correlation<br />
of Precambrian in the Romanian Carpathians. An.<br />
Inst. Geol. Geofiz. LVII, București.<br />
Kräutner, H. G. (1983). Geotraverse H in the East<br />
Carpathians; Stratigraphic correlation forms. In:<br />
“Newsletter “ IGCP Project no. 5 (F. P. Sassi, F.<br />
Szederkenyi, Eds.), Padova.<br />
Kräutner, H. G. (1988). East Carpathians. In: “Precambrian<br />
in younger fold belts” (V. Zoubek, Ed.), pp.<br />
625 - 638. Wiley, Chichester.<br />
Kräutner, H. G. (1996). Eastern Carpathians. In: “<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
Paleozoic Geodynamic domains and their alpidic evolution<br />
in the Tethys “. IGCP Project No. 276 (Papanikolaou<br />
, coord.). Ann. Géol. des Pays Helléniques,<br />
37, p. 336 - 352, Athènes.<br />
Mutihac, V. and Bratu, E. (1965). Fazies und Alter<br />
der Ablagerungen aus dem nordlichen abschnitt des<br />
Ostkarpatischen Ausserrandmulde., Carp. Balk. Geol.<br />
Assoc., VII Congr., Sofia.<br />
Mutihac, V. and Ionesi, L. (1974). Geologia României.<br />
Ed. Tehnică, București.<br />
Săndulescu, M. (1973). Contribuţii la cunoașterea<br />
structurii geologice a Sinclinalului Rarău (french extend.<br />
abstr. ). D. S. Inst. Geol. LIX / 5, București.<br />
Săndulescu, M. (1975). Studiul geologic al părţii centrale<br />
și nordice a Sinclinalului Hăghimaș (french extend.<br />
abstr.). An. Inst. Geol. Geofiz. XLV, Bucureși.<br />
Săndulescu, M. (1976). Contribuţii asupra stratigrafiei<br />
și a poziţiei tectonice a seriilor mesozoice din<br />
bazinul superior al văii Moldova (Carpaţii Orientali),<br />
(french extend. abstr. ), D. S. Inst. Geol. Geofiz. LXII<br />
/ 5, București.<br />
Săndulescu, M. (1988). Cainozoic Geotectonic History<br />
of the Carpathians. Bull. AAPG 45, Tulsa.<br />
Săndulescu, M. (1990). Le flysch crétacé de la zone<br />
du Mont Ceahlău et du bassin du Bicaz. D. S. Inst.<br />
Geol. Geofiz. 74 / 4, București.<br />
Săndulescu, M. and Russo - Săndulescu, D. (1981).<br />
The Ophiolites from the Rarău and Hăghimaș Synclines<br />
- Their Structural Position, Age and Geotectonic<br />
Evolution. D. S. Inst. Geol. Geofiz. LXVI / 5,<br />
București.<br />
Săndulescu, M. and Micu, M. (1988). Oligocene<br />
Paleogeographiy of the East Carpathians. In: “Oligocene<br />
from Transylvanian Basin”, Ed. Univ. Cluj.<br />
Săndulescu, M., Tomescu, C., Iva, M. (1976). Date<br />
noi cu privire la microfaciesurile și biostratigrafia<br />
formaţiunilor mezozoice din Sinclinalul Rarău<br />
(french extend. abstr.). D. S. Inst. Geol. Geofiz. LXII<br />
/ 4, București.<br />
Săndulescu, M., Kräutner, H. G., Balintoni, I., Russo<br />
B12<br />
45 - B12<br />
Volume n° 1 - from PR01 to B15
Volume n° 1 - from PR01 to B15<br />
B12<br />
B12 -<br />
Leader: M. Sandulescu<br />
- Săndulescu, D., Micu, M. (1981). The Structure of<br />
the East Carpathians (Moldavia - Maramureș Area).<br />
CBGA, 12 th Congr., Guide to Excurs., B 1, Inst. Geol.<br />
Geophys., Bucharest.<br />
Săndulescu, Micu, M., Bratu, E. (1987). Stratigraphy<br />
of the Eocene Flysch Formations of the East Carpathians.<br />
In: “Eocene from Transylvanian Basin”, Ed.<br />
Univ. Cluj.<br />
Săndulescu, M., Antonescu, E., Bratu, E. (1992).<br />
Contributions à la connaissance de l’âge du Grès de<br />
Prisaca. Rom. J. Tect. Reg. Geol. 74, Bucharest.<br />
Săndulescu, M., Antonescu, E., Platon, E. (1993).<br />
La Nappe de Macla entre les vallées de Tărcuţa et<br />
Aţa (Monts de Tarcău) - Corrélations régionales et<br />
paléogéographiques. Rev. Roum. Géologie 37, Bucarest.<br />
Săndulescu, M., Mărunţeanu, M., Popescu, Gh.<br />
(1995). Lower - Middle Miocene Formations in the<br />
Folded Area of the East Carpathians. Rom. J. Stratigr.<br />
76, Bucharest.<br />
Stan, N., Tiepac, I., Uscătescu, A. (2000). Petrogenetic<br />
evolution of the Hăghimaș granitoids in geochemical-tectonic<br />
context (Eastern Carpathians, Romania).<br />
Rev. Roum. Géol. 44, 31-50, Bucarest.<br />
Turculeţ, I. (1971). Cercetări geologice asupra depozitelor<br />
jurasice și eocretacice din cuveta Rarău<br />
- Breaza (french extend. abstr.). Inst. Geol., St. Tehn.<br />
Econ. Ser. J, 10, București.<br />
Apuseni Mountains<br />
Avram, S., Lazăr, C., Berbeleac, I., Udubașa, G.<br />
(1988). Evolution of banatitic magmatism in the<br />
Apuseni Mountains and associated metallogenesis. D.<br />
S. Inst. Geol. Geof. 72-73/2, 115-213. București.<br />
Bordea, S. (1992). Stratigrafia depozitelor neojurasice<br />
si cretacice din partea vestică a Munţilor Metaliferi.<br />
Rezumatul tezei de doctorat, 1-26, Universitatea<br />
“Al.I.Cuza” Iași.<br />
Bortolotti, V., Marroni, M., Nicolae ,I., Pandolfi, L.,<br />
Principi, G., Saccani, E. (2002). Intern.Geol. Review<br />
44/10, 938-955, Winston &Son.<br />
Cioflica, G., Lupu, M., Nicolae, I., Vlad, Ș. (1980).<br />
Alpine ophiolites of Romania:Tectonic setting, magmatism<br />
and metallogenesis. An. Inst. Geol. Geof.<br />
56,79-95. București.<br />
Dallmeyer, R., Neubauer, F., Pană, D., Fritz, H.<br />
(1994). Variscan vs Alpine tectonothermal evolution<br />
within the Apuseni Mountains, Romania: Evidence<br />
from 40 Ar/ 39 Ar mineral ages. Rom. J. Tect. Reg. Geol.<br />
75, suppl. 2 (ALCAPA II), 65-76. Bucharest.<br />
Dimitrescu, M. (1995). Variaţia formei galeţilor<br />
metaconglomeratelor paleozoice din Bihorul de Sud.<br />
St. cerc. geologie 40, 3-18. București.<br />
Ellero, A., Leoni, l., Marroni, M., Nicolae, I., Pandolfi,<br />
L, Sartori, F. (2002). Deformation and metamorphism<br />
in the Feneș Nappe (southern Apuseni Mountains,<br />
Romania). C. R .Géoscience 334, 437-354. Paris.<br />
Ianovici, V., Borcoș, M., Patrulius, D., Lupu, M.,<br />
Dimitrescu, R., Savu, H. (1976). Geologia Munţilor<br />
Apuseni. Ed. Academiei, 1-632. București.<br />
Ianovici, V., Giușcă, D., Ghiţulescu, T., Borcoș, M.,<br />
Lupu, M., Bleahu, M., Savu, H. (1969) . .Evoluţia<br />
geologică a Munţilor Metaliferi. Ed. Academiei, 1-<br />
744. București.<br />
Nicolae, I., Soroiu, M., Bonhomme, M. (1992). K-<br />
Ar ages of some ophiolitic rocks from the Southern<br />
Apuseni Mountains and their geologic implications<br />
(Romania). Geol. Alpine 68, 77-83. Grenoble.<br />
Nicolae, I. and Saccani, E. (2003). Petrology and<br />
geochemistry of the Late Jurassic calc-alkaline series<br />
associated to Middle Jurassic ophiolites in the South<br />
Apuseni Mountains (Romania). Swiss. Bull. Min. Petrol.<br />
SMPM 83, 81-96.<br />
Saccani, E., Nicolae, I., Tassinari, R. (2001).Tectonomagmatic<br />
setting of the Jurassic ophiolites from the<br />
South Apuseni Mountains (Romania): Petrological<br />
and geochemical evidence.Ofioliti 26/1, 9-22.<br />
Savu, H. (1980). Genesis of the Alpine cycle ophiolites<br />
from Romania and their associated calc-alkaline<br />
and alkaline volcanics. An. Inst. Geol. Geof. 56, 55-<br />
77. București.<br />
Savu, H., Udrescu, C., Neacșu, V., Stoian, M. (1986).<br />
Petrology, geochemistry and origin of mafic ophiolitic
ocks within the Obârșia Cloșani-Baia de Aramă region<br />
(Mehedinţi Plateau). D .S. Inst.Geol.Geof. 70-<br />
71/1, 183-20. București.<br />
South Carpathians<br />
Antonescu, E. (1973). Asociaţii palinologice caracteristice<br />
unor formaţiuni cretacice din Munţii Metaliferi.<br />
D. S. Inst. geol. LIX / 4, 115-169. București.<br />
Berza, T. and Seghedi, A. (1983). The crystalline<br />
basement of the Danubian Units in the Central South<br />
Carpathians: Constitution and metamorphic history.<br />
An. Inst. Geol. Geof. 61, 15-22. București.<br />
Berza, T. and Iancu, V. (1994). Variscan events in the<br />
basement of the Danubian nappes. Rom. J. Tect . Reg.<br />
Geol. 75, suppl. 2, ALCAPA II, 93-103. Bucharest.<br />
Berza, T., Balintoni, I., Iancu, V., Seghedi, A., Hann,<br />
H. (1994). South Carpathians. Rom. J. Tect. Reg.<br />
Geol. 75, suppl. 2, 37-49. Bucharest.<br />
Berza, T., Constantinescu, E., Vlad, Ș. (1998).Upper<br />
Cretaceous magmatic series and associated mineralization<br />
in the Carpathian-Balkan fold belt. Journ. of<br />
Resource Geol. 48/4, 291-306. Tokyo.<br />
Berza, T., Kräutner, H., Dimitrescu, R. (1983). Nappe<br />
structurein the danubian Window of the Central<br />
South Carpathians. An. Inst. Geol. Geof. 60, 31-39.<br />
București.<br />
Codarcea, Al. (1940). Vues nouvelles sur la tectonique<br />
du Banat méridional et du Plateau de Mehedinţi. An.<br />
Inst. Geol. 20, 1-74. București.<br />
Dallmeyer, R., Neubauer, F., Mocanu, V., Fritz, H.<br />
(1994). 40 Ar/ 39 Ar mineral age controls for the pre-<br />
Alpine and Alpine tectonic evolution of nappe complexes<br />
in the Southern Carpathians. Rom. J. Tect. Reg.<br />
Geol. 75, suppl. 2 (ALCAPA II ), 77-86. Bucharest.<br />
Dimitrescu, M. (200). Histoire déformationelle des<br />
métamorphites carpatiques: Monts du T¸arcu et Collines<br />
de Bocșa. An. Inst. Geol. Rom. 71, 105-106.<br />
București.<br />
Dimitrijevic´, M. (1997). Geology of Yugoslavia.<br />
Barex,1-188. Beograd.<br />
Duchesne, J., Berza, T., Liégeois, J., Vander Auwera<br />
GEOLOGICAL STRUCTURE OF THE ROMANIAN CARPATHIANS<br />
J. (1998). Shoshonitic liquid line of descent from diorite<br />
to granite:the Late Precambrian post-collisional<br />
Tismana pluton (South Carpathians, Romania). Lithos<br />
45, 281-303. Elsevier.<br />
Grünenfelder, M., Popescu, G., Soroiu, M., Arsenescu,<br />
V., Berza, T. (1983). K-Ar dating of metamorphic<br />
and associated rocks in the Central South Carpathians.<br />
An. Inst. Geol. Geof. 61, 31-38. București<br />
Iancu, V. (1982). Lower Supragetic nappes of the Banat,<br />
Moniom-Dognecea zone. D. S. Inst. Geol. Geof.<br />
69/5, 31-36. București.<br />
Iancu, V. (1986). Unités structurales supragétiques et<br />
infragétiques de la partie ouest des Carpates Méridionales.<br />
D. S. Inst. Geol. Geof. 70-71/5, 109-127.<br />
București.<br />
Iancu, V. and Mărunţiu, M. (1994). Pre-Alpine lithotectonic<br />
units and related shear zones in the basement<br />
of the Getic-Supragetic nappes (South Carpathians).<br />
Rom. J. Tect. & Reg. Geol. 75, suppl. 2 (ALCAPA II),<br />
87-92. Bucharest.<br />
Kräutner, H., Berza, T., Dimitrescu, R. (1988) .South<br />
Carpathians. In: “Precambrian in younger fold belts”<br />
(V. Zoubek, Ed.), pp.639-664. Wiley, Chichester.<br />
Kräutner, H. and Krstic´, B. (2002). Alpine and pre-<br />
Alpine structural units within the Southern Carpathians<br />
and the Eastern Balkanides. 27 th Congr. CBGA,<br />
1-8. Bratislava.<br />
Krstic´, B. and Karamata, S. (1992). Terranes of the<br />
Eastern Serbian Carpatho-Balkanides. C. R. D. S.<br />
Soc. Serbe Géol., livre jubil. (1891-1991), 57-74.<br />
Beograd.<br />
Liégeois, J., Berza, T., Tatu, M., Duchesne, J. (1996).<br />
The Neoproterozoic Pan-African basement from the<br />
Alpine Lower Danubian nappe system (South Carpathians,<br />
Romania). Prec. Res. 80, 281-301. Elsevier.<br />
Manolescu, G. (1937). Etude géologique et<br />
pétrographique dans les Munţii Vulcan (Carpates<br />
Méridionales, Roumanie). An. Inst. Geol. 18, 79-112.<br />
București.<br />
Pantic´, N. (1963). Fitostratigrafia devonovah I kamennougolnah<br />
otlojenii Karpato-Balkan (Vostocinaia<br />
Serbia). CBGA, Congr. V (1961), Com. St. III / 2,<br />
B12<br />
47 - B12<br />
Volume n° 1 - from PR01 to B15
Volume n° 1 - from PR01 to B15<br />
B12<br />
B12 -<br />
Leader: M. Sandulescu<br />
107-115. București.<br />
Pavelescu, L., Pavelescu, M., Bercia, I., Bercia, E.<br />
(1964). Cercetări petrografice și structurale în defileul<br />
Jiului între Bumbești și Iscroni. D. S. Inst. Geol.<br />
50 / 1, 43-60. București.<br />
Russo-Săndulescu, D., Berza, T., Bratosin, I., Ianc, R.<br />
(1978). Petrological study of the Bocșa banatitic massif.<br />
D. S. Inst.Geol. Geof. 64 / 1, 105-172. București.<br />
Russo-Săndulescu, D., Vâjdea, E., Tănăsescu, A.<br />
(1986). Significance of K-Ar radiometric ages ob-<br />
tained in the banatitic plutonic area of Banat. D. S.<br />
Inst. Geol. Geof. 70-71 / 1, 405-417. București.<br />
Savu, H. (1970). Stratigrafia și izogradele de metamorfism<br />
din provincia metamorfică prebaikaliană<br />
din Munţii Semenic. An. Inst. Geol. 38, 223-311.<br />
București.<br />
Săbău, G. (1994). Lithostratigraphic and metamorphic<br />
correlations: a tentative way of exploring the<br />
early history of the Getic crystalline. Rom. J. Petrol.<br />
76, 119-128. Bucharest.
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