Tectonostratigraphy of the Tercan-Cayirli Basin: Implications for the neogene-Quaternary tectonic deformation of the Northeast Anatolian Block, Turkey

Abstract

The Tercan-Cayirli Basin is located in the Northeast Anatolian Block, and is bordered by the North Anatolian fault zone to the south and the Northeast Anatolian fault zone to the north. The basin developed on top Of a Southerly obducted. Upper Cretaceous ophiolitic melange and low-grade metamorphic thrust sheets during Oligocene time. The lower sequences of the basin consist of coarse-grained continental clastics, reflecting foreland basin development. An Early Miocene transgression covered eastern Anatolia; deposition during this event corresponds to the upper sequences in the Tercan-Cayirli Basin. Late Miocene-Early Pliocene time is represented by basaltic-andesitic volcanism and continental sediments deposited in foreland basins. Coarse fluviatile clastics were deposited in strike-slip fault-controlled basins during the Quaternary. Tectonic deformation styles of the Northeast Anatolian Block and the Tercan-Cayirli Basin are shaped by Late Miocene-Early Pliocene thrust tectonics and Late Pliocene-Quaternary strike-slip tectonics, respectively. Kinematic analyses of fault slip data show NNW-SSE directions of movement. The tectonic deformation style of the Northeast Anatolian block reflects the combined effect of Late Miocene-Early Pliocene southward accretion and Late Pliocene-Quaternary eastward escape of the block toward the Caucasus.