The Balkan Fold-Thrust Belt: an overview of the main features

Pages: 
pp. 29-47
Sofia University “St. Kliment Ohridski”, 15 Tsar Osvoboditel Blvd, 1504 Sofia, Bulgaria
Sofia University “St. Kliment Ohridski”, 15 Tsar Osvoboditel Blvd, 1504 Sofia, Bulgaria
Geological-Paleontological Institute, Geoscience Department, Basel University
Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria
Abstract: 

The Balkan Fold-Thrust Belt is a part of the northern branch of the Alpine-Himalayan orogen in the Balkan Peninsula and represents a Tertiary structure developed along the southern margin of the Moesian Platform. The thrust belt displays of two clearly distinct parts: an eastern one dominated exclusively by thin-skinned thrusting and a western part showing ubiquitous basement involvement. A wide transitional zone is locked between both parts where the structural style is dominantly thin-skinned, but with significant pre-Mesozoic basement involvement in the more internal parts. For the western thick-skinned part the poorly developed syn-orogenic flysch is a characteristic feature that along with the very restricted development of foreland basin suggests a rather limited orogenic shortening compared to the eastern part of the belt. The Tertiary Balkan Fold-Thrust Belt originated mainly through a basement-driven shortening and this is explained by the occurrence of compatibly oriented reactivated basement weak zones of pre-Carboniferous, Jurassic and Early Cretaceous ages. The proposed re-definition of the Balkan thrusts system and internal structure of the allochthons also call for significant re-assessment of the existing schemes of tectonic subdivision.

Keywords: 

retrobelt, thin- vs. thick-skinned thrusting, foreland basin, subthrust tectonics

VOLUME 42 (1-3)/December 2013

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria

Sofia University “St. Kliment Ohridski”, 15 Tsar Osvoboditel Blvd, 1504 Sofia, Bulgaria
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Sofia University “St. Kliment Ohridski”, 15 Tsar Osvoboditel Blvd, 1504 Sofia, Bulgaria
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Geological-Paleontological Institute, Geoscience Department, Basel University
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria

National Museum of Natural History, Bulgarian Academy of Sciences, 1 Blvd. Tsar Osvoboditel, 1000 Sofia, Bulgaria
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School of Geology, Aristotle University, 54124 Thessaloniki, Greece
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School of Geology, Aristotle University, 54124 Thessaloniki, Greece; E-mail: lilits@geo.auth.gr

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113, Sofia, Bulgaria
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113, Sofia, Bulgaria

Albanian Geological Survey, Rruga e Kavajes, 153, Tirana, Albania
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Institute of Geosciences, Water, Energy and Environment, Polytechnic University of Tirana, Tirana, Albania

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria
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University of Architecture, Civil Engineering and Geodesy, Hristo Smirnenski Blvd. 1, 1046 Sofia, Bulgaria