Geological and geomorphological characteristics of the Posolsky Bank and the Kukuy Griva, Lake Baikal

Detailed geological and geophysical investigations of the underwater topography of Lake Baikal, based on single-channel high-resolution seismic profiling and bathymetric survey using an ELAC SeaBeam 1050 multibeam echosounder, as well as the data obtained during diving of MIR deep-sea manned underwater submersibles determined the morphological characteristics of the Posolsky Bank and Kukuy Griva elevations suggesting that their elevated parts represent fragments of the once common delta surface of the Selenga River. The current relief of these structures resulted from the joint activity of tectonic and underwater erosive processes. Sediments at the base of the slope of the Kukuy Griva are likely to be no older than 1.8 Ma.