Abstract:
Taking the supergene geochemical behavior of such elements as Cu and W in Yanshan period and Jinning period of rocks during the process of weathering as the study object, the authors conducted the investigation, and the results can offer an effective geochemical basis for the development of regional geochemical prospecting and the establishment of geological-geochemical prospecting model for the magmatic hydrothermal type tungsten-copper deposit. Through the study of CIA that reflects the weathering degree, the estimation of components of gain and loss in the process of weathering, the content changes of such ore-forming elements as tungsten and copper in different media, and the supergene geochemical behavior of the large ion lithophile elements, the authors have reached some conclusions: The elements leaching of the two periods of rocks is related to the intensity of the weathering in the Shimensi tungsten-copper mining area. The alkali metals and the alkali-earth metal elements have been subjected to considerable leaching in the soil profile whereas W, Cu and some other ore-forming elements are significantly concentrated in soil horizon B. W, Cu and some other ore-forming elements gradually increase in the process of weathering from rock to soil and then to the stream sediments. Therefore, excellent sampling media seem to be the first-order stream sediments and soil horizon B for geochemical prospecting in the Jiuling W, Sn, Cu and Mo polymetallic ore concentration area in northern Jiangxi Province. These effective prospecting means can make a new breakthrough in the ore concentration area.