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The Beyşehir-Hoyran Nappes, one of the tectonostratigraphic units of the Taurides, are thought to be originated from the Izmir-Ankara Ocean (northern branch of Neotethys). In this study, Late Paleozoic rock units from the blocks of Beyşehir-Hoyran Nappes were studied in detail using foraminiferal assemblages in two different locations from the southwest of Karaman City (southern Turkey). In both places, blocks/slices and pebbles of various origins are embedded within a highly sheared matrix of Late Cretaceous Age, and the whole unit can be regarded as a sedimentary mélange. The ages of the blocks from the southwest of Karaman City range from the Late Serpukhovian (Late Mississippian) to Late Capitanian (Middle Permian) with some depositional breaks (e.g., Bashkirian, Kasimovian). Combined with the previous data from the Mersin Mélange, which also include the remnants of the Beyşehir-Hoyran Nappes, our new findings suggest that a shallowing-upward sequence, characterized by a shallow water environment with foraminifera-bearing limestones, was deposited over the Tournaisian pelagic sequence in the Beyşehir-Hoyran Nappes till the Early Moscovian (Early Middle Pennsylvanian). This shallowing-upward sequence in the Beyşehir-Hoyran Nappes could be related to the Late Paleozoic Glaciation on the Gondwana supercontinent (Glacial II), which resulted in a sea-level drop and deposition of platform carbonates during the Viséan–Early Moscovian (Middle Mississippian to Early Middle Pennsylvanian) time interval. The absence of the main part of the Middle-Upper Pennsylvanian deposits (continental phase during the Middle Moscovian–Middle Gzhelian) in the Beyşehir-Hoyran Nappes can be mainly attributed to the occurrence of a mantle plume and partially to the effect of Late Paleozoic Gondwanan Glaciation (Glacial III). Progressive uplifting by the buoyant mantle plume material has resulted in rifting at the center of the basin where the Beyşehir-Hoyran Nappes have deposited. The rifting process led to tectonic destabilization of the platform in the basin, causing accumulation of the Upper Gzhelian (uppermost Pennsylvanian) detrital limestone with broken and abraded foraminiferal shells. Following this, deep basinal conditions prevailed during the Late Asselian–Kungurian (Early Permian), as revealed in the Mersin Mélange, where radiolarian cherts are associated with continental within-plate lavas of extreme incompatible trace element enrichment. Similar processes were responsible for the continual deposition of detrital limestones in the same basin until the end of Late Capitanian (Middle Permian). Based on all these, the uplifting process followed by rift-related volcanic rocks and detrital limestones can be interpreted as the opening of the Izmir-Ankara Ocean (northern Neotethys). [ABSTRACT FROM AUTHOR]

A multidisciplinary approach combining multiscale geological-structural analyses (from field to microscale) and clay mineral transformations (clay mineralogy, illite and chlorite "crystallinity" and b cell dimension (b0) of K-white mica) was adopted to unravel the tectono-metamorphic evolution of low- and very low-grade tectono-metamorphic units from the Intra-Pontide suture zone in northern Turkey. The mineralogical study allowed to better evaluate the structural stacking outlined during the geological mapping, leading to distinguish three tectono-metamorphic units, two in epizone (Daday and Emirköy units) and one in anchizone (Çifter Unit) metamorphic conditions. The mesostructural and microstructural analyses suggest a polyphase tectonic-metamorphic evolution. The different macroscopic features observed between the two units characterized by the same epizone metamorphism, can be justified by the evidence that these metamorphic conditions were acquired during the last stages of exhumation in the Daday Unit, while they constrained the metamorphic-peak conditions in the Emirköy Unit. Contemporary analyses and comparison between structural and mineralogical data have thus proven to be a powerful tool to investigate the low-grade and very low-grade metamorphic environments, allowing at the same time to solve the apparent contradictions deriving from the mineralogical study and to significantly improve the detail of the geological mapping in the field. [ABSTRACT FROM AUTHOR]

A number of suture zones exist in Turkey, which is believed to represent the closure of Paleo and NeoTethyan oceanic basins. Regarding the development of the latter oceanic entity, namely Neotethys, the geodynamic evolution of the Intra-Pontide branch, the northernmost one of a number of oceanic basins remains enigmatic. The Intra-Pontide Suture Zone in Northwest Turkey includes several tectonic units most of which are characterized by the occurrence of mafic rocks with distinct geochemical signatures. In this paper, the mafic rocks collected from four of these units (the Domuz Dağ Unit, the Saka Unit, the Daday Unit and the Arkot Dağ Mèlange) have been studied in detail along two selected transects. The Domuz Dağ Unit is characterized by amphibolites, micaschists and marbles, which have been overprinted by low-grade metamorphism.The Saka Unit is in turn represented by an assemblage of slices of amphibolites, marbles and micaschists metamorphosed under upper amphibolite facies metamorphic conditions in the Late Jurassic time. In these units, the amphibolites and their retrograded counterparts display E-MORB-, OIB- BABB- and IAT-type signatures. The Daday Unit is characterized by metasedimentary and metamafic rocks metamorphosed under blueschist to sub-greenschist facies conditions. The metamafic rocks comprise actinolite-bearing schists and Na-amphibole-bearing varieties possibly derived from basaltic and gabbroic protoliths. They have a wide range of chemical compositions, displaying N-MORB-, E-MORB-, OIB- BABB- and IAT-type signatures. The Arkot Dağ Mèlange consists of a Late Santonian assemblage of slide-blocks mainly represented by basaltic lithologies showing affinities ranging from N-MORB- and IAT- to BABB-type magmas. The geochemical signature of the studied mafic rocks indicates that the tectonic units documented along the two studied transects of the Intra-Pontide Suture Zone have been derived from a supra-subduction zone. This hypothesis corroborates the available data collected from the Aylı Dağ Ophiolite Unit cropping out in the westernmost studied transect. This finding can provide new insights for the reconstruction of the geodynamic history of the Intra-Pontide domain. [ABSTRACT FROM AUTHOR]

A correction to the article "Geological setting and geochemical signatures of the mafic rocks from the Intra-Pontide Suture Zone: implications for the geodynamic reconstruction of the Mesozoic Neotethys," by Kaan Sayit and colleagues in the December 23, 2015 issue is presented.