Grain-scale experimental study of samples using the large-scale micro-channel system survey technique for the cold, semi-arid grassland landscape: A case study of the rare Li-Be ores in the Qiemoge Mountain

The Qiemoge Mountain area in Tianjun County, Qinghai Province has a cold, semi-arid grassland landscape. A pegmatite belt with a width of 300~500 m and an intermittent extended length of 7 km has developed on the surface of this area. The rare Li-Be ores have been discovered during the current exploration in this area. To provide a reliable geochemical basis for the prospecting of rare metals and rare earth elements (REE) in areas with similar landscapes, this study conducted the grain-scale experiment and validity investigation in this study area using the large-scale micro-channel system geochemical survey technique. Based on the 1∶25,000 geochemical survey, grain sizes of -4~+ 20 meshes, -4~+ 40 meshes, -10~+ 40 meshes, and -10~+ 60 meshes were adopted in sampling for the experimental study in the zones bearing pegmatite veins. The contents of Cu, W, Sn, Be, Li, Nb, Rb, Zr, La, and Y were analyzed. The results show that relevant elements exhibited significant enrichment and dispersion characteristics and the geochemical distribution of these elements agreed well with the geological and mineral characteristics when grain sizes of -4~+ 40 meshes and -10~+ 40 meshes were adopted for the sampling of Be, Li, Nb, Rb, and Zr, grain sizes of -10~+ 40 meshes were adopted for the sampling of rare earth elements such as La and Y, and grain sizes of -10~+ 60 meshes were adopted for the sampling of nonferrous metal elements such as Cu, W, and Sn. The results of this study prove that the large-scale micro-channel system survey technique can obtain significant results in the geochemical prospecting of rare metals and REEs in areas with similar landscapes.