Pliocene vertebrate locality of Çalta, Ankara, Turkey. 1. Sedimentation and lithostratigraphy

A fossil bearing volcaniclastic sequence at Çalta, Central Anatolia, Turkey was investigated using a modified facies and architectural element analysis. This was done in order to describe the local lithostratigraphy and to shed light on depositional environments and palaeogeography of the area during time of formation. Four main depositional environments were recognized: (1) distal alluvial fan; (2) fluvial channel; (3) overbank and floodplain and (4) pond environment. These environments characterize the evolution of landscape from a relatively steep to land surface of low relief in the more distal part of an alluvial plain. The main fossil beds occur in the floodplain and ponded deposits at levels that show best developed paleosols.