Sedimentary Architecture of the Undeformed Lower Miocene Gorendagi Submarine Fan Deposits From Neo-Tethys Ocean (Eastern Anatolia-Turkey): Tectonic Control on Preservation of Fan Morphology

Abstract

Submarine fan deposits which constitute the remnants of Neo-Tethys are widely observed throughout the Bitlis-Zagros Suture Belt. Most of these deposits are located in the Arabian-Eurasian collision zone and have been intensively deformed due to ongoing tectonic activity. In this study, the depositional characteristics and preservation processes of the undeformed, Lower Miocene Gorendagi Submarine Fan deposits, associated with this zone, are studied with respect to their sedimentological and structural features. These deposits display feeder or distributary channels, overbank, and lobe sediments and classical Bouma Ta-d divisions. They are subdivided into inner, middle, and outer fan, according to sedimentological and morphological properties. Sand-rich submarine fan deposits have 39 m thickness and approximately 2 km of lateral extension. The submarine fan body is bounded to the north and the south by two reverse faults, namely the Ozyurt and Goktepe faults. These faults formed an accommodation space where the fan was deposited and also caused the deepening of the basin. The position and activity of these oppositely inclined reverse faults, which form a triangular zone, are the main reason for preservation of the original fan morphology in the Gorendab Submarine Fan. Our results indicate that the Gorendab Submarine Fan represents one of the last sequences deposited before the closure of the southern branch of the Neo-Tethys Ocean and also the most well-preserved.