V. A. Shakhverdov, M. V. Shakhverdova (A. P. Karpinsky Russian Geological Research Institute)

HYDROGEOCHEMICAL FEATURES AND TEMPERATURE REGIME OF THE LAKE BAIKAL BOTTOM ZONE CAUSED BY NATURAL HYDROCARBON MIGRATION PROCESSES

The paper describes features of hydrogeochemical composition of bottom waters and temperature regime in the bed zone of Lake Baikal. Estimated coefficient or temperature gradient is proposed, which allows the analysis of the temperature regime, regardless of the depth of sampling of bottom water and soil. It is identified that objects of natural hydrocarbon migration and near-bottom hydrogeochemical anomalies are accompanied by anomalous values of the temperature gradient. The obtained results suggest that the destruction of gas hydrate with active release of methane occurs because of local bottom heating. The processes are accompanied by active substance mobilization and its involvement in migration. The temperature regime in the northern basin of the lake differs from the rest of the lake that may indicate the absence of near-bottom occurrences of gaseous crystalline hydrate in this part of the lake.
Keywords: Lake Baikal, gas hydrate, hydrocarbons, geochemistry, temperature measurements.