Oligocene molasse sedimentation in the Central Taurides: Records of the onset of extensional tectonic regime

Yıl 2020, Cilt: 163 Sayı: 163, 47 - 76, 15.12.2020

Ayhan Ilgar Tolga Esirtgen Banu Türkmen Bozkurt Serap Demirkaya

https://doi.org/10.19111/bulletinofmre.681218

Cited By: 1

Öz

The lacustrine units have been deposited in the Ermenek, Bucakkışla, Korucuk and Çamlıyayla basins in the Central Taurides since early Oligocene. In this study, structural features and stratigraphical properties of Oligocene basins have been described in detail and the lacustrine units have been dated. Regional geological interpretations have been made by using tectono-stratigraphic and age data of the basins. Lacustrine Oligocene sedimentation in these basins, which were opened on the tectonic units of Taurides due to normal faults, constitute the first records of the sedimentation occurring under the extensional tectonic regime after the orogeny of the Central Taurides. All the pre-Oligocene units that had been emplaced in the region due to a north-south compressional movement in the Central Taurides, continued to be compressed until the end of Eocene, and completed their orogenic development as napped structures. The bedrock units, reaching the maximum elevation, have been subjected to “orogenic collapse” due to the strain or gravity forces as a result of an interruption or termination of the compression which lasted until the end of Eocene. Thus, “orogenic collapse” basins have started to be formed in the Central Taurides since Oligocene. The orogeny and the compressional tectonic regime forming the Taurides lasted until late Miocene in the Eastern Taurides. On the other hand, extensional basin formation since early Oligocene on the Taurus units, which had been emplaced in the region due to nappe tectonics, indicates that a new tectonic period has started in the Central Taurides.

Anahtar Kelimeler

Taurus orogeny, Orogenic collapse, Lacustrine deposits

Teşekkür

This study was carried out in the scope of “Geology and Paleogeographic Development of the Neogene Rocks in Adana-Mut Basin” project conducted between 2009-2012 by the Department of Geological Research of the General Directorate of Mineral Research and Exploration (MTA). Palynological investigations were conducted by Assoc. Prof. Dr. Mine Sezgül Kayseri Özer. The first draft of the manuscript was reviewed by Prof. Dr. Cihat Alçiçek, Dr. Volkan Özaksoy, Dr. Oktay Parlak and Ali Ergen. Prof. Dr. Yaşar Eren, Prof. Dr. Ulvi Can Ünlügenç and Assoc. Prof. Dr. Serkan Üner made valuable contributions. We would like to thank to the Referees for carefully reading our article and for giving such constructive comments which substantially helped improving the quality of the paper.

Kaynakça

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