Depositional Properties and Paleoclimate of a Middle-Upper Pleistocene Fan Delta Sequence in the Bor Plain, Central Anatolia, Turkey.

The Bor Plain, which is located in the Middle Kızılırmak subregion of the Central Anatolia Region, extends 14 km toward the west of Niğde. The fan delta deposition system in the southwest of the Bor Plain was formed on the fault-controlled foothills of Mt. Keçiboyduran. The fandelta sequence shows that a paleolake formed during a phase because of the mineralogical content and frequently changing facies. Additionally, clay minerals and herbaceous plants reflecting humid and arid climatic conditions illustrate the lake-level changes. Six changes in the lake level occurred from marine isotope stage (MIS) 7 to (MIS) 5. Three major high stands occurred in the paleolake at the lowest and middle parts of the sequence. The first high stand was a stepwise transgression between ~240 and ~230 ka., and the second high stand was between ~200 and ~195 ka. The third high stand was characterized by a short transgression at 182 ka. After this stage, the lake receded significantly at 127 and 105 ka, indicating climatic control over the water level changes. In the transition from the Middle to Late Pleistocene, a revival of volcanic activity in the Leşkeri monogenic volcanic mass released volcanic material, affecting sedimentation. Volcanic rocks increase dramatically in the upper section of the fandelta during an interval that coincides with low lake-level fluctuations. [ABSTRACT FROM AUTHOR]