Estimation of the long-term slip, surface uplift and block rotation along the northern strand of the North Anatolian Fault Zone: Inferences from geomorphology of the Almacik Block


Yıldırım C. , Tuysuz O.

GEOMORPHOLOGY, cilt.297, ss.55-68, 2017 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

The Almacik Block is one of the key morphotectonic units in the eastern Marmara Region associated with the long-term slip partitioning within the North Anatolian Fault Zone (NAFZ). In this study, we provide new geomorphic reconstructions of offset drainage basins, morphometric analysis of topography, and longitudinal profiles of the rivers crossing different flanks of the Almacik Block. Our geomorphic reconstructions of offset drainage basins along the Hendek and Karadere faults implymean offset of 23 +/- 0.4 km and 8.4 +/- 0.7 km, respectively, during the Quaternary. Our dataset also imply that slip partitioning occurs in a broader zone than previously proposed, and that the total 10.7 +/- 0.6 km offset along the Hendek and Karadere faults of the northern strand must be taken into account for long-term slip partitioning in the Eastern Marmara Region. Together with previously suggested 10 km offset along the southern strand (Yaltirak, 2002), 16 +/- 1.0 km offset along the middle strand (Ozalp et al., 2013) and the 52 +/- 1.0 km offset along the Mudurnu Segment of the northern strand (Akbayram et al., 2016) our newly proposed geomorphic markers raise the cumulative offset in the eastern Marmara region associated with the NAF to 89 +/- 1.0 km since the Latest Pliocene - Quaternary. In addition to these lateral displacements, our morphometric analysis and longitudinal profiles of the rivers imply up to 1130 +/- 130 m surface uplift of the Almacik Block as a combined result of vertical displacement within the deformation zone of the northern strand of the NAFZ. Finally, by assuming that river basins act as passive deformation markers, our basin azimuth analyses imply 20 degrees +/- 2 degrees clockwise rotation of the Almacik Block associated with the NAFZ. (C) 2017 Elsevier B.V. All rights reserved.