^{207}Pb-^{206}Pb, ^{40}Ar-^{39}Ar and Apatite Fission-Track Geothermochronology Revealing the Emplacement, Cooling and Exhumation History of the Karaçayır Syenite (N Sivas), East-Central Anatolia, Turkey

Authors: DURMUŞ BOZTUĞ, ESRA TÜRKSEVER, MATT HEIZLER, RAYMOND J. JONCKHEER, MARION TICHOMIROWA

Abstract: The Karaçayır syenite, intruding the Palaeozoic crustal metamorphics and unconformably overlain by Upper Paleocene to Eocene Tokuş formation in the north of Sivas (east-central Anatolia), has been studied with respect to ^{207}Pb-^{206}Pb single zircon evaporation, biotite ^{40}Ar-^{39}Ar, and apatite fission-track geothermochronology. ^{207}Pb-^{206}Pb single zircon evaporation dating yields an age of 99.0±11.0 Ma (Cenomanian-Turonian) which is considered to be the intrusion age. Biotite ^{40}Ar-^{39}Ar age determination gives a cooling age of ca. 65 Ma. Apatite fission-track dating, combined with T-t modeling based on track-length distribution data, determines a fast tectonic exhumation with an uplift rate of > 1 mm/a which occurred 58-61 Ma ago. This Middle Paleocene fast tectonic uplift is considered to have resulted from a compressional regime induced by the collision between the Tauride-Anatolide platform (TAP) and the Eurasian plate (EP) along the İzmir-Ankara-Erzincan (İAE) suture zone following the closure of the north-dipping subducted İAE ocean which belongs to northern Neo-Tethyan realm. This compressional regime has also formed the peripheral foreland basins in central Anatolia.

Keywords: single zircon ^{207}Pb-^{206}Pb, biotite ^{40}Ar-^{39}Ar, apatite fission-track, exhumation history, Karaçayır syenite, Sivas, Turkey

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