Stratigraphy and tectono-sedimentary evolution of the Upper Cretaceous-Tertiary sequence in the southern part of the Malatya Basin, East Anatolia, Turkey

Abstract

The Malatya Basin is situated on the southern Taurus-Anatolian Platform. The southern part of the basin contains a sedimentary sequence which can be divided into four main units, each separated by an unconformity. From base to top, these are: (1) Permo-Carboniferous; (2) Upper Cretaceous-Lower Paleocene, (3) Middle-Upper Eocene and (4) Upper Miocene. The Upper Cretaceous-Tertiary sedimentary sequence resting on basement rocks is up to 700 m thick. The Permo-Carboniferous basement consist of dolomites and recrystallized limestones. The Upper Cretaceous-Lower Paleocene transgressive-regressive sequence shows a transition from terrestrial environments, via lagoonal to shallow-marine limestones to deep marine turbiditic sediments, followed upwards by shallow marine cherty limestones. The marine sediments contain planktic and benthic foraminifers indicating an upper Campanian, Maastrichtian and Danian age. The Middle-Upper Eocene is a transgressive-regressive sequence represented by terrestrial and lagoonal clastics, shallow-marine limestones and deep marine turbidites. The planktic and benthic foraminifers in the marine sediments indicate a Middle-Upper Eocene age. The upper Miocene sequence consists of a reddish-brown conglomerate-sandstone-mudstone alternation of alluvial and fluvial facies. During Late Cretaceous-Early Paleocene times, the Gunduzbey Group was deposited in the southern part of a fore-arc basin, simultaneously with volcanics belonging to the Yuksekova Group. During Middle-Late Eocene times, the Yesilyurt Group was deposited in the northern part of the Maden Basin and the Helete volcanic arc. The Middle-Upper Eocene Malatya Basin was formed due to block faulting at the beginning of the Middle Eocene time. During the Late Paleocene-Early Eocene, and at the end of the Eocene, the study areas became continental due to the southward advance of nappe structures. The rock sequences in the southern part of the Malatya Basin may be divided into four tectonic units, from base to top: the lower allochthon, the upper allochthon, the parautochthon and autochthonous rock units. (c) 2006 Elsevier Ltd. All rights reserved.