Quaternary geology and active tectonics of Cuma ovası (Menderes) basin

Main objective of this study is to reconstruct the Quaternary structural evolution of the Cumaovası basin, combined with correlation of the west Anatolia extensional province. The study consists of basin deposits, basin faults and associated kinematic analysis. Cumaovası basin, which located at the western parts of Gediz and Küçük Menderes grabens, is a 5-17-km wide and 35-km long, NNE-trending, assymetric pull-apart basin that formed under the control of normal and strike-slip faults. Basin infill is characterized by two alluvial sucssesions separated by local unconformity. These are named as Görece formation and Alluvium and developed upon metamorphic rocks of Menderes Massif, sedimentary rocks of the İzmir-Ankara zone and Neogene volcano-sedimantery units. Both of the northern and southern margin-bounding faults of the Cumaovası basin are oblique-slip normal faults with left-lateral strike-slip components, while the western margin is bounded by dextral strike-slip faults with normal- and/or reverse components. These faults are mapped and identified as the Buca, Değirmendere, Orhanlı, Yeniköy and Kunerlik faults, respectively. The fault kinematic analysis along this master faults within the Cumaovası basin show that there are three different stress regime in Plio-Quaternary time: (1) NNE-SSW extension directions with WNW-ESE compression directions, (2) NE-SW extension directions, (3) NNW-SSE extension directions with WSW-ENE compression directions.