Neotectonic structures in İzmir Gulf and surrounding regions (western Turkey): Evidences of strike-slip faulting with compression in the Aegean extensional regime

Abstract

Of single channel, 70 km, and 900 km of multi-channel seismic reflection data show that İzmir Gulf and surrounding regions are widely deformed by N–S to NE–SW trending active transpressional strike-slip faults, reverse faults and some E–W normal faults. Normal faults are mapped offshore Karaburun–Foça, in inner part of İzmir Gulf; offshore Alaçatı–Teke and offshore Kuşadası delimiting the southern scarp of Lesvos basin, İzmir basin, northern scarp of Ikaria basin and continuation of Küçük Menderes Graben, respectively. Normal faults are cut by strike-slip faults. The major strike-slip faults are the N–S oriented Karaburun reverse fault bordering İzmir Gulf on the west and uplifting the Karaburun Peninsula and the NE–SW oriented strike-slip Tuzla Fault extending from Doğanbey Promontory towards Seferihisar ridge onland. This fault pattern can be explained by pure-shear model indicating that the area is under E–W compression, N–S extension, NE–SW and NW–SE strike-slip deformation. Moreover, Tuzla Fault has a regional importance. It separates NE–SW trending structures of the study area from E–W oriented Gediz and Küçük Menderes grabens and probably continues towards to İznik at north constituting a transition zone between northern transpressional region and southern extensional region in the western Anatolia–Aegean Sea.