The Magma-Hydrothermal System at Mutnovsky Volcano, Kamchatka Peninsula, Russia

What is the relationship between the kinds of volcanoes that ring the Pacific plate and nearby hydrothermal systems? A typical geometry for stratovolcanoes and dome complexes is summit fumaroles and hydrothermal manifestations on and beyond their flanks. Analogous subsurface mineralization is porphyry copper deposits flanked by shallow Cu-As-Au acid-sulfate deposits and base metal veins. Possible reasons for this association are (1) upward and outward flow of magmatic gas and heat from the volcano’s conduit and magma reservoir, mixing with meteoric water; (2) dikes extending from or feeding towards the volcano that extend laterally well beyond the surface edifice, heating a broad region; or (3) peripheral hot intrusions that are remnants of previous volcanic episodes, unrelated to current volcanism. These hypotheses are testable through a Mutnovsky Scientific Drilling Project (MSDP) that was discussed in a workshop during the last week of September 2006 at a key example, the Mutnovsky Volcano of Kamchatka. Hypothesis (1) was regarded as the most likely. It is also the most attractive since it could lead to a new understanding of themagma-hydrothermal connection and motivate global geothermal exploration of andesitic arc volcanoes