One more drilling experiment, as part of the Baikal Drilling Project, was carried out in 1998 on the Akademichesky Ridge. Drilling was performed to the subbottom depth of 670 m in 333 m of water at 53°44′48″ N, 108°24′34″ E. Continuous coring was completed to 600 m with a core recovery of 95%. The BDP-98 section is composed of alternating biogenic (diatom-bearing) and terrigenous (diatom-barren) muds. This rhythmic structure traceable along the entire core formed in response to alternating cold and warm climates. Variations in diatom abundance correlate with biogenic silica, magnetic susceptibility, water content, and density profiles. Proceeding from paleomagnetic studies and analysis of the Earth’s orbital frequencies in the climatic record of the core, the sediments at a depth of 600 m were dated at 103 Ma BP. The results of core studies provide a basis for further detailed climate reconstructions in Central Asia from the late Middle Miocene and make it possible to refine the geological history of the Baikal rift. 
