Composition and Origin of Lavas from the Minami-Hiyoshi Submarine Volcano (Mariana Arc)

Resumo

This work is a link in a series of studies of Late Cenozoic submarine volcanoes of the island arcs in the western part of the Pacific Ocean, representing the first detailed Russian-language description of the material composition of the Minami-Hiyoshi submarine volcano, which is involved in the Hiyoshi volcanic complex (the norther5th cn part of the Mariana arc). This study was based on rock material dragged from the volcano during the 5th cruise of the R/V Vulkanolog. New original data on the structure, chemical and mineral compositions, and origin of volcanic lava were obtained. It was shown that all the lava flows studied are genetically linked and originated from the same magma chamber. Structural–petrographic differences in the lava flows are explained by different dynamics in the melt transportation to the surface of the bottom of the ocean.