New data on paleogeomorphology of the Buzachi Peninsula (Western Kazakhstan)

Abstract

At the end of Early Pliocene the Buzachi Peninsula and Ustyurt formed a single plateau armoured with Sarmatian and Pontian limestones. At Middle Pliocene the plateau was eroded under arid climatic conditions due to a catastrophic drop of the Caspian Sea level. A deep erosional valley (at the place of the present Kaidak and Dead Kultuk solonchaks) separated the Buzachi Peninsula from the Ustyurt, the Buzachi plateau being divided into series of flat-topped remnants with landslides on the slopes, later on the remnants were completely destroyed and only some landslides' blocks and masses were conserved in lowest parts of the landscape. The Middle Pliocene topography (including the landslides' masses) was conserved under the cover of marine sediments of the Baku, Khazar and Khvalyn stages when almost all the Buzachi Peninsula was flooded.