The zone of Tertiary autonomous activation of the Balkan peninsula
is characterized by a specific structural plan, multiphase volca-
nic-intrusive magmatism and interesting mineral deposits.
Striking transcurrent faults can be recognized from air and satel-
lite pictures, striking in the same direction as the zone of acti-
vation, as well as systems of smaller parallel faults, systems of
diagonal jagged faults and systems of straight, tension faults. A
special characteristic of the zone of autonomous activation is its
many ringlike structures. These megastructures correspond to broad,
gentle arches, are elliptical or circular in shape and have a dia-
meter of 60 to 100 km. Their internal structure features a wealth
of forms. They are built of concentric ringlike segments, and some-
times have the appearance of a coil, The central parts are usually
raised, the other rings are alternately lowered and raised. The ra-
dially arranged faults separate the internal parts of the megastruc-
ture into sector blocks. These structures are contoured along the
periphery by depressions which are-either bow-shaped or oval-shaped.
Within the megastructure there are numerous smaller ringlike forms
ranging from several hundred meters to a few kilometers in diameter.
The first signs of magmatic activity in the zone of Tertiary auto-
nomous activation had already occurred at the end of the Bocene,
but it is still not clear what connection they have with this zone.
The magmatism culminated in the Miocene, while it gradually calmed
down in the Pliocene, occasionally extending into the Quaternary.
The magmatic rocks correspond to the volcanic-intrusive granodiori-
te complexes, chemically they belong to the Ca-alkali rocks and in
later phases are rich in potassium. Besides dacite-andesites, we
also find trachyandesites, quartz-latites, latites, trachybasalts,
trachytes and subordinate leucite rocks (lamprophyric facies). The
rocks are accompanied by pyroclastics, agglomerates and breccia.
Tuffs are extremely rare..Intrusives of quartzdiorite, granodiorite
and quartzmonconites are, in principle, synchronous with analogous
volcanic rocks. Magmatic rocks are consolidated at the subvolcanic-
volcanic level, in the process of which plutons are formed as "high
plutons", According to more recent ideas, granites in the zone of .
autonomous activation were formed by metasomatic transformation of
granodioritic plutons.
There are
Tertiary :
end niobi
granites |
genetical:
dioritic
and hemat.
The coppe:
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(Rudnik),
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by the di:
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Middle Ea:
