Tolmachevsky active magmatic center (South Kamchatka) and its heat-power capacity as estimated by deep geophysical surveys

Abstract

The structure of the Earth’s crust and upper mantle has been estimated by using geologic-geophysical cross-sections developed along two orthogonal geophysical profiles in the area of the Tolmachevsky active magmatic center. Comprehensive geophysical data have revealed the existence of an intrusive massif of predominantly intermediate-medium-felsic composition whose formation is accounted for by the presence of powerful heat flows and local melting sites. A swarm of small earthquakes reported in 1987-1988 was triggered by the advance of magma in the zone of the assumed eruptive fissure. Meteoric waters interact with the high-temperature media through the infiltration zone, which results in intense hydrothermal activity including the formation of steam-hydrothermal occurrences. The area of the proposed intrusive body is a promising zone for a high-temperature geothermal reservoir.