The reports, introduced on scientific session of the First International Kuril-Kamchatka field workshop, are published in this book. Papers are devoted to studying the geothermal and mineral resources of modern volcanism areas and, first of all, to researching the long-living ore-forming hydrothermal-magmatic systems of insular arcs. The following scientific themes in six sections are submited: (1) geothermal resources, common problems; (2) structure, thermal and power supply of hydrothermal-magmatic systems; (3) petrology, mineralogy and geochemistry of rocks; (4) geochemistry and dynamics of gases and natural waters; (5) ore mineralization in geothermal systems; (6) seismicity of geothermal regions and geotechnological aspects. The tendencies of development of researches, the new ideas and concrete actual materials on an example of geothermal fields of Kuril Islands and Kamchatka, and also New Zealand, Philippines, USA etc., are discussed. The new tasks of geothermal and mineral resources studying are formulated.
The book is prepared for specialists in Earths sciences, geologists, volcanologists, hydrogeologists, geochemistris, perologists, mineralogists etc.; for teaches, post-graduate students and students, all readers which are interested by problems of a geothermie and hydrothermal mineral-ore formation.

This book presents new data on the composition, genesis and metal content of hydrothermal solutions in the areas of active volcanism and their significance in mineral formation.