New Data on the Composition of Ophiolite Complexes on Karaginskii Island (Eastern Kamchatka)

Abstract

The geochemistry and composition of peridotite rock-forming minerals from blocks in the serpentinite mélange of Karaginskii Island have been studied. The composition features of the rock-forming minerals are indicative of the fact that they represent abyssal peridotites of the mid-oceanic ridges that did not undergo remelting under suprasubduction conditions. According to the geochemical data, these rocks were subject to metasomatic alterations under mantle conditions in the suprasubduction setting, which were caused by metasomatizing melts and/or fluids generated in the subduction zone.