Evolution of the Post-Collisional Cratonic Basins in Eastern Turkey

Abstract

A number of cratonic basins developed as a result of continent—continent collision in Eastern Taurus. During this collision, some changes in the rate of continental convergence considerably affected the evolution of these cratonic basins. Following the Late Eocene collision, the Oligocene transgression started as a result of a decrease at the rate of continental convergence. The weaker effect of the convergence rate during the Middle—Late Oligocene resulted in lithospheric deformation forming some troughs and uplifts. Further decrease in the effect of the convergence rate during the Uppermost Oligocene, caused the widespread Early Miocene transgression. During Langhian, a sudden increase in the effect of the convergence rate gave rise to the uplifting of the whole region above the sea level. In Serravalian—Tortonian, continental and marine transgressions took place, due to the relatively decreasing effect of the convergence rate. However, convergence rate which was considerably effective in the Uppermost Tortonian, played an important role in the formation of Anatolia. A partial decrease in the convergence rate during the Early—Late Pliocene provided the deposition in continental basin conditions. In the Uppermost Pliocene, the convergence rate increased again and as a result of this, the tectonic lines representing the Uppermost Tortonian phase were displaced. The effect of convergence rate which was relatively low during the Early—Late Pleistocene provided restricted continental depositional conditions. Increasing effect of convergence rate from the Late Pleistocene to the present—day is responsible for the active faults. This evolutionary scheme of the post—Eocene basins proves that the collision has been continuing since Late Eocene.