SULFUR MINERALIZATION OF MODERN GEOTHERAMAL SYSTEM IN YANGBAJING BASIN OF XIZANG
Zhang xigen (MGMR Institute of Hydrogeology and Engineering Geology)
The geothermal heat fluids circulating about within the Yangbajing basin of Xizang were probed with respect to their geochemistry , gas composition and isotopic characters, coupled with the studies of the related sinterite, rocks and minerals. The results indicated that the water of the head fluids was sourced dominantly from meteoric water and locally from underground depths, that the mineralizing materials were related mainly to the leaching of the trapping rocks and that few mounts, such as volatile components, were caused by heat diffusion of shallow seated magmatic activities. Sulfur mineralization took place mostly at places where the geothermal heat fluids could release pressure to move, an argument that is based on knowledge of the mineralizing features and distribution and on establishment of a metallogenetic model for the geothermal system. Sulfur and sulfides owed their origins, to a great extent, to microbial contributions in the geothermal basin.