Isotopic and thermochronological data were recently obtained from the footwall of the Büyük Menderes detachment ranges from ± Ma (ZFT) to ± Ma (Ap U-Th/He), and they can be grouped in three different time intervals. These results are well explained by the Alaşehir type-rolling hinge mechanism, which suggests active rotated initial normal fault during successive normal fault development of the graben formation. This paper suggests that the Alaşehir type-rolling hinge mechanism is applicable to the Büyük Menderes graben by using field observations, published isotopic/thermochronological and subsurface data. It also contributes to the long-lasting discussion about the activation problem on the low-angle normal faults. | Turkish Journal of Earth Sciences Turkish J Earth Sci 2021 30 322-340 http earth TÜBİTAK Research Article doi yer-2003-2 Alaşehir type - rolling hinge mechanism in the northern margin of Büyük Menderes Graben Evidence from seismic reflection and recent thermochronological data 1 2 1 Fevzi Mert TÜRESİN Gürol SEYİTOĞLU 1 Department of Geological Engineering Tectonics Research Group Ankara University Ankara Turkey 2 Turkish Petroleum Company TPAO Ankara Turkey Received Accepted Published Online Final Version Abstract Isotopic and thermochronological data were recently obtained from the footwall of the Büyük Menderes detachment ranges from Ma ZFT to Ma Ap U - Th He and they can be grouped in three different time intervals. These results are well explained by the Alaşehir type-rolling hinge mechanism which suggests active rotated initial normal fault during successive normal fault development of the graben formation. This paper suggests that the Alaşehir type-rolling hinge mechanism is applicable to the Büyük Menderes graben by using field observations published isotopic thermochronological and subsurface data. It also contributes to the long-lasting discussion about the activation problem on the low-angle normal faults. Key words Western Anatolia extensional tectonics Büyük Menderes detachment fault seismic profile rolling hinge 1. Introduction was also pointed out in a study suggesting a 3D model for One of the most debated issues in structural geology is the the formation of Turtleback structures and a new name development of high-angle vs. low-angle normal faults. the Alaşehir type-rolling hinge model was introduced The mechanical model of Anderson 1942 suggests that to explain the activation on the rotated low-angle normal normal faults form and slip with high dip values gt 45 fault Seyitoğlu et al. 2014 Figure 1a 1c which is however many studies report low-angle normal faults .
