Helium Isotopes in the Underground Springs of East Tuva

摘要

East Tuva, one of the most seismoactive zones of the Altai-Sayan region, is located at its eastern flank and adjoins riftogenic structures of the southwestern termination of the Baikal rift zone (BRZ). East Tuva incorporates a volcanic area including one of the largest recent lava fields (East Tuva lava highland) in Central Asia and extended valley lava flows [1]. This zone is considered volcanically active and hazardous. The lava field is controlled by the NNE-oriented fault system, which also governed the formation of the southern present-day Bilin-Busiingol graben. The area of East Tuva and adjacent Mongolia is characterized by a sharp change in the stress-strain state of the lithosphere. Numerous thermal veins [2] and some geothermal estimates of heat flow [3] attest to high temperatures in the Earth's interior in this area.