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PERIADRIATIC MARGIN
The South Adriatic-Ionian Zone is built up of Cretaceous shallow
marine limestones and anhydrites, also accompanied by dolomites in the
upper parts; next, of transgressive Middle Eocene limestone and
Eocene-Oligocene flysch. In the area of the map presented, this zone is
thrust over by the narrow and highly tectonized Budva Zone which
has a rather condensed column comprising Lower Triassic sediments; next,
Middle Triassic rocks with Anisian flysch and Ladinian volcanics in one
part of the terrain, and carbonates in the rest of it. The locally missing
Upper Triassic is followed by the neritic Jurassic. The thin Lower
Creaceous, sometimes even absent, is overlain by Cenomanian-Senonian
limestone and predominantly Oligocene flysch.
THE DINARIDES
The Dalmatian-Herzegovinian Zone (formerly inadequately designated
as the High Karst Nappe) has been thurst over the Budva Zone. The
direction and distance of movement of this zone is still a matter of
speculation. In the map area this zone is represented by the Stara Crna
Gora (Old Montenegro) Overthrust. The Middle Triassic resembles that found
in the Budva Zone. The Upper Triassic is characterized by a carbonate
platform consisting of shallow water carbonates whose deposition went on
till the end of the Cretaceous and terminated with Paleogene foraminiferal
limestones. The Sarajevo Sigmoid, in the map area known as the Kuci
overthrust, is a conspicuous belt of mesozoic flysh. It consists of thin
Permian and Triassic clastics and neritic carbonates; next, of an
unconformable sequence of limestones that range from the Upper Jurassic to
the Turonian, and of transgressive Durmitor flysch of Senonian age, whose
fold fabric is characteristically intricate. Going NW, the composition of
this belt becomes increasengly complex, the onset of flysch sedimentation
falling in the Jurassic. The East Bosnian-Durmitor block represents
a composite pile of nappes, the front of the Durmitor nappe being its SW
boundary.Below this nappe, consisting mainly of Paleozoic and Triassic
rocks, there is another nappe dominantly of Triassic sedimnets with
volcanics, revealed by tectonic windows near Berane. The tectonic windows
in the latter display in turn the Durmitor flysch whose displacements
exceed 40 km. Numerous thin nappe sheets and klippen can also be observed
further NE showing that this area is built up of several units differing
in development. The Lower Triassic is mostly represented by sandstone. In
the Anisian, dolomites and bioclastic limestone with red Bulog limestone
predominate, while the volcanites close the sequence. The Ladinian
generally starts with cherts and tuffs, and is followed by comparatively
thin cherty limestone, dolomite and reef limestones. During the Upper
Triassic a carbonate platform with a thick limestone sequence developed in
the SW of this area, while in the NE (Romanija and Jahorina Mts) only
rather thin Triassic-Jurassic cherty limestones were deposited. In the SW
the Jurassic is mostly represented by limestones, whereas in the NE it is
built up of Ophiolitic Mélange, the two kinds of rock being separated by
a narrow flysch zone. The Cretacous is generally absent. The Drina-Ivanjica
Element is made up of a Paleozoic basement exibiting a strong
Hercynian tectogenesis with NE-SW trending axes; next, of a Triassic
carbonate platform the parts of which were gravitationally transported in
the Ophiolitic Mélange during the Upper Jurassic. These are followed by a
shallow marine Upper Cretaceous in the SW parts, and a transgressive
Senonian sequence (rudite, rudist limestone, pre-flysch, Kosovska
Mitrovica flysch) along its boundary with the Vardar Zone.
THE VARDAR ZONE
is the most complicated belt of the Balkan Peninsula. It is composed of
several blocks of diverse composition, geological history and provenience,
and includes characteristic oceanic elements. One of these, the Srem
Block that can be observed at Fruska gora Mt, is built up of partly
metamorphosed Mesozoic rocks and Creataceous flysch in one of its
tectonically separated domains, and of shallow marine deposits in the
other, while tectonic zones consist of ophiolites. The Jadar Block
rests on the Jadar Paleozoic and shows no traces of Hercynian folding. The
Triassic is represented by the Porphyrite-Chert Formation, while the Upper
Cretaceous consists of flysch. Tertiary magmatites, i.e. the granitoids of
Cer, Boranja and Bukulja, the volcanites of Borac and Kotlenik are
outstanding features of this block. No agreement has yet been reached as
to the age and geotectonic position of metamorphites near Arandelovac
(Bukulja and Vencac Mts.)
Further south the Vardar Zone can be subdivided into three parts. These
are: (1) The External Vardar Subzone built up of blocks highly
differing in composition, rich in ultramafites (Stolovi Mt, etc); next, of
Senonian Ophiolitic Mélange, with metamorphism ranging up to the
Cretaceous. This subzone also includes granitoids of Zeljin and Kopaonik,
and volcanic rocks; (2) the Central Vardar Subzone which covers a
conspicuous belt of Lower Cretaceous Gledici para-flysch resting on
Jurassic ophiolitic mélange. Methamorphism here varies on age; (3) the Inner
Vardar Subzone which comprises crystaline schists of unknown age, the
Senonian Toplica flysch, and the Lece volcanics.
THE OPHIOLITE BELT
separates the East Bosnian-Durmitor Block from the Drina-Ivanjica Element.
It carries large olilstoplaques of Triassic limestone gravitationally
transported from the NE and E (Devetak, Zlatibor, Zlatar, Giljeva, Mokra
Gora, Zljeb); next, large masses of ultramafites (Krivaja-Konjuh,
Zlatibor), and blocks of oceanic crust (Dobrun) embedded in the ophiolitic
mélange and covering it. In its southern part this belt separates the
Dinarides from the Hellenides and is thrust over Mirdita.
THE HELLENIDES
are present in the map area only to a very limited extent. The Debar
Zone consists mainly of Triassic limestone and gypsiferous Paleogene,
while the West-Macedonian (Korab) Zone is made up of low rank
metamorphics, mostly of Paleozoic age.
THE SERBO-MACEDONIAN MASS
comprises two complexes of crystalline schists: (1) the lower, highly
metamorphosed and pre-Cambrian in age, and the upper (Vlasina) complex of
green schists ranging in age from Riphean to Lower Paleozoic. These rocks
were intruded by granitoids whose age ranges from Paleozoic (Vlajna,
Bujanovac) to Tertiary (Surdulica). The position of the Jastrebac
granitoid is still under dispute.
THE CARPATHO_BALKANIDES
The Superagetikum (Golubac-Luznica zone) is made up of green
schists, Devonian flysch, Permian red sandstones, Mesozoic limestones, and
Jurassic flysch. It has been thrust over the Getikum, a large
complex nappe, which builds up most of the eastern territory of Serbia. It
is subdivided into several zones which partly differ in their geological
history and were, therefore, interpreted even as separate nappes (Suva
Planina, Kucaj, Timok, Tupiznica, Porecka reka, Stara planina, Vidlic).
The Getikum consists of Proterozoic-Cambrian schists, Ordovician
and Silurian low rank metamorphics, Devonian flysch, Permian and Triassic
red sandstones, and Middle Triassic-Cretaceous limestones, as well as the
Upper Cretaceous volcanic sedimentary formation in the Timok area. While
in Romania large Getikum klippen (Bahna, Mehedinci) are preserved, in
eastern Serbia only rather small klippen of the Sip and Tekija crystalline
are open to view.
The Infragetikum embraces ultramafics underlyng these klippen;
next, Zaglavak and Deli Jovan gabbroes with adjacent metamorphites, and
the Sinaia beds.
The Danubikum represents an autochtone in relation to
these units. The oldest rocks comprised in it are green schists with
numerous igneous veins, overlain by Upper Carboniferous strata and a
transgressive succession of rocks ranging in age from Liassic to
Cretaceous. At the close of the Cretaceous, flysch begins its development
in the Miroc domain.
THE PANNONIAN BASIN
has a highly diverse basement consisting of crystalline schists and
granitoids in south-eastern Banat, northern Banat and northern Backa, of
Mesozoic rocks in most of the central and southern Banat, and of
ophiolites along the margins of subzones and block of the Vardar Zone. The
basin is filled with lacustrine and marine deposits of Tertiary and
Quaternary age. |
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