EVOLUTION OF THE HYDROGEN-ISOTOPE COMPOSITION IN THE MAGMATIC ORE-FORMING PROCESS IN ERDENETUIEN OBO DEPOSIT

Abstract

n the largest copper-molybdenum deposit in Asia, the Erdentuin Obo in the Mongolian People's Republic, there are igneous rocks that contain isotopically unusually 'light' hydrogen as compared with other deposits of the same type. This paper reports on an analysis of the factors specifically controlling the isotope composition of hydrogen in the magma system that generated this large-volume mineral deposit. The isotope analyses (32 of rocks, and four of hornblende and biotite) were done in Shinshu University, Japan.