Neslihan OCAKOĞLU, Emin DEMİRBAĞ

İzmir Körfezi ve dolaylarının aktif tektonizmasının sismik yansıma verileri ile incelenmesi

İzmir Körfezi, Alaçatı-Doğanbey-Kuşadası açıklarının aktif tektonizmasını incelemek amacıyla toplanan ve işlenen 975 km uzunluğundaki çok ve tek kanallı sismik yansıma kesitlerinden bölgede birincil K-G ve KD-GB gidişli genellikle sıkışma bileşenli aktif doğrultu alımlı fay sistemleri, ters faylar ve ikincil D-B gidişli normal faylar haritalanmıştır. Körfezin KKB-GGD gidişi Karaburun ters fayı ile sınırlanırken, güneyde Seferihisar yükselimi KD-GB doğrultulu Tuzla fayı kontrolündedir. Körfezin D-B uzanan iç kısmını güneyde izmir normal fayı sınırlar. Bölgedeki aktif fay sistemlerinin gelişimi batıya kaçan Anadolu'nun Yunanistan engeli sonucu saatin tersi yönünde dönüşü ve Hellen yayına doğru GB hareketi sonucu oluşan kabaca D-B sıkışma, KD-GB gerilme rejimi ile açıklanmakladır.

Investigation of the active tectonism of İzmir Gulf and surrounding area by seismic reflection data

To investigate the active tectonism of İzmir Gulf and offshore Alaçalı-Doğanbey-Kuşadası, 975 km multi-channel and single-channel seismic reflection profiles collected and processed. Data show that the study area is widespread occupied by N-S to NE-SW trending master faults characterized as strike-slip faults with generally compression component, reverse faults and secondary E- W trending normal faults. These faults are also very compatible with the active faults of surrounding onland area. While the outer part of İzmir gulf is controlled by N-S oriented Karaburun reverse fault, the Seferihisar horst at the southern offshore area is bordered by NE-SW oriented strike-slip Tuzla fault zone with positive flower character. The direction of the Karaburun fault changes from NNW-SSE to N-S along the eastern coast of Karaburun Peninsula with accompanying a change in its fault type from positive flower structure to reverse fault. Also, Tuzla fault zone is observed offshore Doğanbey Promontory with mostly reverse fault component on the seismic sections where its orientation changes from NE-SW to N-S. On the other hand, the inner part of the gulf is deliniated by E-W trending Izmir normal fault. Development of active fault patterns in the study area is explained by the prevention of westward motion of Anatolia by Greece, the occurrence of a compression between them, counter-clock wise rotation and SIV motion and NE-SW extension of Anatolia towards to the Hellenic arc.

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