PHYSICOCHEMICAL PARAMETERS OF THE OLDEST BONINITE MELTS

Abstract

Ophiolites of the southeastern Sayan region, the oldest formations in Central Asia (1020 Ma), include unique information on early stages of Paleoasian Ocean evolution. The presence of boninites in the ophiolites indicates that a suprasubduction environment similar to that of the present-day Pacific island-arc systems existed as early as 1 Ga ago. Therefore, investigations of magmatic systems responsible for the formation of such ancient rock complexes are of great scientific interest. In order to elucidate physicochemical parameters of boninite melts of the southeastern Sayan region, we examined melt inclusions in chrome spinels of boninite samples from rock complexes of the “dike-indike” type in the Dunzhugursk sector.