Ancient valleys at plains of East Mongolia

Abstract

A network of ancient dry channels exists at plains of East Mongolia. Space images and field studies revealed the network to be a part of Silin-Gol, Urgan-Gol, Adzarga-Gol drainage basins, the rivers now flowing from the Big Khingan and Nukut-Daban ridges. The rivers inflowed into Buir-Nur and Dalainor lakes. As geomorphological observations proved, the dry valleys were flooded when the high level of floodplain was forming, i. e. in early Holocene. Some dry valleys are associated with the 2nd terrace of the Kerulen River, Downstream from the knee-like bend near the Mongolia-China border the ancient valley of the river goes southward towards the Kurai solonchaks. The drainage took place during the Late Pleistocene.