Glacial geomorphology and glacial lakes of central Transbaikalia, Siberia, Russia

Abstract

A glacial geomorphological map is presented covering the poorly investigated mountainous region of central Transbaikalia, Russia. Interpretation of geomorphology is achieved using remotely sensed data (SRTM digital elevation model, Landsat 7 ETM+ satellite imagery and Google Maps). Glacially modified terrain is mapped together with moraines, glacial lineations and meltwater channels, in order to provide an estimate of the area affected by glaciation. The glacial landform record varies across the mapped region implying that the character of glaciation was not uniform in the area. Several moraine generations occur in the main valleys and at some places glaciers blocked the drainage routes, which resulted in the formation of glacial lakes. The largest, Glacial Lake Vitim, was dammed by a glacier lobe blocking the Vitim valley in the Kodar Range. A distinct fossil shoreline of Glacial Lake Vitim occurs along a substantial part of the former shore at a level of 840 m a.s.l. A col through which the lake drained to the River Nercha occurs at an elevation consistent with the shoreline level of 840 m a.s.l. The existence of another glacial lake in the Chara basin is inferred from mapped delta surfaces and a probable blockage of the Chara River by advancing valley glaciers. The rich and diverse geomorphology and the sedimentary record of glacial lakes represent a potential for more detailed studies of the glacial and climate history of this remote region.