The Udokan Plateau volcanic field occupies a broad area about 400 km ENE of the northern tip of Lake Baikal. Quaternary volcanism here represents the latest manifestation of activity dating back to the Miocene covering an area of 3000 sq km at the eastern margin of the Baikal Rift System. Late-Pleistocene to Holocene volcanic centers are concentrated along three major lineaments, and many eruptions were localized along fissures trending NW-SE and NE-SW. Dated Holocene volcanic centers are located on a 20-km-long line at the SW side of the volcanic field, but Holocene cinder cones also occur in the NE Udokan Plateau. Seismic activity has been recorded at depths of 15 to 20 km beneath some of the cones. The Udokan volcanic field is dominated by basaltic cinder cones, but basal trachytic ignimbrites are also overlain by lava domes and flows, and trachytic maars were formed during the final stages of activity. The latest dated eruption took place at Chepe volcano about 2200 years ago.