SOURCE AREAS AND STRUCTURAL CHARACTERISTICS OF THE MIOCENE FRAGMENT OF THE MONASTYRSKY FLYSCH SECTION, NORTHERN PART OF THE ABKHAZ ZONE OF THE GREATER CAUCASUS

Presented here are the results of a comprehensive study of flysch successions common in the northern Abkhaz zone of the Greater Caucasus (Monastyrsky flysch). There have been micropaleontological analysis (nannoplankton), U-Pb dating of detrital zircons (LA-ICP-MS), and structural-kinematic studies. The fragment of the Monastyrsky flysch section, previously assigned to the Oligocene, has been dated back to the Miocene (or younger) epoch, its source areas have been identified, and an approach has been proposed for interpretation of flysch succession deformations, genetically related to the Monastyrsky fault. The Monastyrsky fault is paragenetically linked to the formation of the Vorontsov nappe and apparently remained active until recent times. The Vorontsov nappe, as well as the associated deformations, are not older than the Late Miocene. Study results of detrital zircons from sandy siltstones of the Miocene fragment of the Monastyrsky flysch have indicated that this flysch is not synorogenic with the Caucasus neoorogen. Most of the zircon grains from these rocks were most likely transported from platform-like structures northward of the Greater Caucasus orogen (ancient East European and young epi-Hercynian Scythian platforms) and their surrounding fold structures.

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