Thia monograph provides a systematic catalogue description of all 97 known submarine volcanoes and aeamounts in the Kurile island arc, using materials of the R/V "Vulkanolog" six voyages. Interpretations of their morphostructural features are based on echo sounding, seismic reflection profiling, and characteristics of the magnetic field. Compositions have been determined for 80 of the volcanoes, including petrographic and geochemical data, using dredged material.
During concurrent study of subaerial and submarine volcanoes regularities in their spatial-structural distribution, transverse and longitudinal petrogeochemical, mineral, and isotopic zoning, and xenolith distribution in the lavas have been recognized. Volcanic activity is distributed in the frontal and rear-arc zones. These data are used to develop a model for magma generation with two zones of magma generation related to two levels of volatile separation from the subducting lithospheric plate.

The geological and geophysical research carried out during the five cruises of R/V/ Vulkanolog in the 1980s and early 1990s provided new evidence of the structure and evolution of the Chernye Bratya volcanic massif. Five phases have been identified in its evolution. The first phase which began in the Early - Middle Pleistocene, or possibly Neogene, involvel the generation of a major shield-shaped, mostly laval, volcanic massif with dimensions 30 km by 35 km. The secondphase seems to have been a catastrophic explosive eruption producing the older caldera (Gorshkov Outer Caldera) of dimensions 15 km by 20 km. It is not younger than the mid-Late Pleistocene. A large volcanic structure formed during the third phase in the north and central parts of the older caldera, filling most of the caldera and overlapping its rim. A major explosive eruption occurred during the fourth phase producing the younger caldera (Gorshkov Caldera) of dimensions 7.5 km by 11.5 km. The generations time of that caldera corresponds to a powerful burst of acid explosive volcanism in the Kuril-Kamchatka region about 45.000 to 30.000 years ago. The final phase involved high volcanic activity within the younger caldera producing the present-day volcanic edifices of Chirpoy and Brat Chirpoev islands near the caldera rim. The total volume of ejecta discharged in the area may be in excess of 1000-1300 km 3; of these, 400-600 km 3 consist of pyroclastic material produced by the caldera-generating eruptions.