Late Paleozoic-Early Mesozoic paleotectonics of the northern Arabian Plate (SE Turkey) and its role in the Paleozoic petroleum system

Abstract

The Carboniferous compressional deformation of the Arabian Plate has been causally linked with the Hercynian orogeny. However, this epeirogenic movement occurred far from the Arabian plate. Instead, the Gondwana-directed subduction of the Paleo-Tethys oceanic crust may be the controlling factor of the Carboniferous structural development of southeast Turkey (the northern Arabian Plate). The tectonic activity resulted in uplift and widespread erosion of a large area and produced granitic intrusions, metamorphism, folding, and faulting. The compressional event was intermitted by theback-arc spreading of the Neo-Tethys Ocean (Middle Permian-Triassic) that occurred because of the detachment of the Cimmerian supercontinent from the Gondwana margin. The spreading of the Neo-Tethys caused the Arabian Plate to be subjected to extensional tectonism. The tectonic overprints of these epeirogenic events on the structural fabric of southeast Turkey have not been studied in detail. Innovations in subsurface imaging techniques, wireline logs, and sufficient-quality data enable the depiction of the traces of the Carboniferous compression and the subsequent Permian–Triassic regional extension. This study explores the structural remnants of the Carboniferous compression and the Permian–Triassic extension in southeast Turkey and their impact on the Paleozoic petroleum system. In conclusion, the Carboniferous, SW- and EW-oriented compressional forces led to major uplift, inversion, and substantive erosion in southeast Turkey. The regional uplift confined the Silurian-sourced oil exploration activities to a narrower area due to the denudation of the Silurian units towards the Carboniferous Arches. Subsequently, the opening of the Neo-Tethys yielded en-echelon NW and WNW-trending horsts and grabens bounded on both sides by normal faults, resulting in the northeastward thickening of the syn-rift units. The horst structures allow hydrocarbon accumulation in the Ordovician Bedinan Formation sandstones tectonically juxtaposed with the Silurian source rock.