EXTENTS OF THE NORTH ANATOLIAN FAULT IN THE YZMIT, GEMLIK, AND BANDIRMA BAYS

Extents of the North Anatolian Fault in the Izmit, Gemlik, and Bandırma Bays

Aykut Barka, Ismail Kusçu

ITU, Faculty of Mining Department of Geology, Ayazağa, Istanbul, TURKEY
MTA, Ankara, TURKEY

Abstract

High resolution shallow seismic reflection profiles, surveyed by MTA Sismik-1 in the Izmit, Gemlik and Bandmna bays, in 1984, were re-examined in order to understand geometry and kinematics of the northern and middle strands of the North Anatolian Fault. We used the pull-apart model to detect the course of the strands. We concluded that this approach fits well with the fault patterns and all three strands seems to have identical fault geometry and kinematics. GPS measurements geomorphology, bathimetry and tickness of sediment in the basins, and historical earthquake records in the eastern Marmara Sea region show that slip rate is higher along the northern strand than the middle strand suggesting higher earthquake risk along the northern strand of the North Anatolian Fault.

Keyword: Shallow seismic reflection profiles, lzmit, Gemlik and Bandırma Bays

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