Geodynamic importance of the strike-slip faults at the eastern part of the Anatolian Scholle: Inferences from the uplift and slip rate of the Malatya Fault (Malatya-Ovacık Fault Zone, eastern Turkey)

Abstract

Controversy remains over when present-day configuration of the Anatolia boundary faults came into existence, and the issue of what are the driving forces of the Anatolian westward motion. The NW-striking dextral and NE-striking sinistral second-order strike-slip faults at the eastern part of the Anatolian Scholle play a crucial role within these long-lasting discussions, and the NE-striking sinistral Malatya–Ovacık Fault Zone (MOFZ) is particularly important in this ongoing debate. Although the MOFZ is defined as one of the intra-plate structures, it has been proposed that it was an inter-plate fault between the Anatolia and Arabian plates from the latest Miocene to mid-Pliocene and that it has been inactive during the last ca. 3.5 Ma. This study provides results from the first morphochronology-based uplift and slip rate estimates on the Malatya Fault within the southern section of the MOFZ. The cosmogenic isochron burial and cosmogenic depth burial of ages from the sinistrally offset Tohma River remnant terraces enabled us to calculate 1.0 ± 0.01 and 1.12 ± 0.01 mm/yr minimum and maximum horizontal slip rates, respectively, for the last 1.4 ± 0.1 Ma. Furthermore, we conclude that the 96 ± 11 m/Ma mean uplift has been driven by the Malatya Fault. Integrated interpretation of the findings of this study and available data on both the MOFZ and other strike-slip faults at the eastern part of the Anatolian Scholle support the hypothesis that they are plate-boundary related active deformation belts that originated from paleotectonic structures during the tectonic escape of the Anatolian Scholle.