Application of exploration geochemistry data to identify anomalies in a plateau region: a case study from the Xiongcun district in the Gangdese metallogenic belt, Tibet, China

This paper describes the discovery of porphyry Cu-Au ore bodies (No. 2 and No. 3) in Xiongcun, Tibet, China, through the investigation of stream sediments, soils and rocks. The study area (Xiongcun), located in the city of Xigaze, has a complex topography due to its complicated geological background. The Xiongcun No. 1 ore body will soon be mined, and it has been 15 years since its discovery. However, recent research on stream sediments, soils and rocks around the No. 1 ore body has revealed notable Cu anomalies on the periphery. With the successful application of exploratory geochemistry data in the anomaly locations, the No. 2 and No. 3 ore bodies have been revealed. The ore reserves of the No. 2 and No. 3 ore bodies are estimated to reach 1.64 million tons of Cu, more than 80 tons of Au and 200 tons of Ag. We expect that our findings will not only enhance the understanding of the reanalysis of anomalies surrounding the discovered deposits but also contribute to the evaluation of the ore-prospecting potential of this plateau region.

Formation of secondary nonsulfide zinc ore in Cho Dien Pb-Zn deposits

In Viet Nam, non-sulfide zinc ore in the Cho Dien deposit has been exploited for a long time. Up to the present, zinc ore remains the major exploited ore in Cho Dien. There are numerous studies of Pb-Zn ore in Cho Dien. However, most of the studies have dedicated only to description of mineralogical and chemical composition of Pb-Zn ore. There has been no publication on this non-sulfide zinc ore. Based on the mineralogical studies, the content of Pb and Zn in groundwater determined by reflective microscope, SEM, EPMA and ICP-MS methods, the study explained the formation of secondary non-sulfide zinc ore in the Cho Dien deposit. Strong weathering process makes the upper part of ore bodies completely oxidized. Difference in geochemical behavior of lead (Pb) and zinc (Zn) in the oxidation process of Pb-Zn ore is the reason to form non-sulfide zinc ore in the Cho Dien deposit. 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