Türkiye Jeoloji Bülteni

Stratigraphy of the Gürün Autochthon (Between Gürün and S ar iz), Eastern Taurus-SW Sivas (Turkey)

Abstract: In this study the stratigraphical aspects of the Gürün autochthone between Gürün and Sanz part havebeen investigated. In the area, between time interval of Paleozoic and Tertiary, the 14 different units have been differentiated. The lower part of the Gürün autochthone (relative autocthone) is represented by rock units of the Upper Devonian and Upper Permian. Gümüşali formation (Upper Devonian), is composed of sandstone, quartzite, limestone, dolomite and shale and Yığılıtepe formation (Upper Permian) consist of limestone and dolomite. The Carboniferous and LowerPermian is not represented by any units. The boundary relation between Yığılıtepe formation and, recrystallized limestone, clayey limestone, marl, sandstone of Katarası formation (Lower Triassic) is an unconformity. The presence ofMiddle Triassic has not been detected.The firstly differentiated units of the Upper Triassic and Lias, rock units; The Toycu Tepe formation (UpperTriassic) is composed of algae limestone and dolomitic limestone while the Çukuryurt formation (Lias) is representedby conglomerate/breccia, sandstone, algaecoral limestone, and shale. Yüceyurt formation of Middle JurassicCenomanian age is overlying the Çukuryurt formation with an angular unconformity. This unit consists of algae limes tone, dolomitic limestone and dolomite. The lower levels of Turonian-Coniacian and Santonian are not presend. TheUpper Santonian-Campanian (Yaniktepe formation) is represented by conglomerate/breccia, rudist limestone.The Akdere formation (Upper Campanian-Maastrictian) transitional to Yaniktepe formation is composed ofconglomerate/breccia, calcarenite and clayey limestone.In the study aera, The Adbalpman formation (Paleocene-Lower Eocene) locally trasitional with underlyingAkdere formation and is composed of dominant pebbly sandstone whose pebbles are conglomerate/breccia, calcarenite,clayey limestone, cherty nodule marl, Demiroluk formation (Lutetian) locally transitional with Abdalpmari formation isrepresented by conglomerate/breccia, Nummulite bearing limestone and marl. These rock units are overlain by an angular unconformity, which the youngest overlying units are conglomerates of Gövdelidağ formation (Upper EoceneLower Miocene) and sandstone, marl and limestone of the Gürün formation (Miocene).