Southeast Jiang Weng Waves Of Gold Ore Material Components, A Preliminary Study

The Wenglang gold deposit lies in Congjiang country of Southeastern Guizhou, and its geotectonic position is along the adjacent area between Jiangnan Orogen and Yangtze landmass located in Northeastern Youjiang Orogen. The main strata exposed in the mine district are Jialu Formation, Wuye Formation and Fanzhao Formation of Xiajiang Group of Proterozoic. The gold ore body is mainly hosted in the mid-upper strata of Jialu Formation, which is primarily controlled by regional detachment structure plane growing in the contact zones between the first and second segments of Jialu Formation(that is, Wenglang-Dihu detachment structure plane belt) and NWW-trending Dang torsion fault. Moreover, the whole ore body is dominated by the in-between alteration zone.On the basis of predecessors' work, the authors choose the Wenglang gold deposit as the main study area, detailedly discussing ore chemical composition, mineralogy, rock structure and texture, etc.; for the first time discovering chalcocite and baritite; initially finding out that the chief metallic materials are natural gold, pyrite, chalcopyrite, magnetite, galenite, sphalerite, hematite and limonite distributing in oxidized zone, the chief nonmetallic minerals are quartz, chlorite, sericite, biotite. In addition, applying the combined macro- and micro-means, the microscopic feature and composition of the above-mentioned minerals are studied in detail. Through preliminary investigation of mineral structure and texture, the authors think that there are many kinds of mineral structure, primarily disseminated, grainy, splinter-shaped, irregular, secondly subtle magnetite vein that infilled the minerals—vein structure; also discover totally eight types of mineral structure, that is, idiomorph, subhedral, xenonorphism, infill, metasomasis, poikilitic, crustose.Moreover, REE of the regional dolerite and the ore are compared, and the result is that REE patterns of the both are essentially similar, which indicates that the ore-forming fluids are possibly from the deep. Corresponding with REE tracer effects and hydrogen and oxygen isotope studies of adjacent areas, it's supposed that the main source of the ore-forming fluids of the Wenglang gold deposit is magma water, mixed with a small amount of meteoric water.