Application of Lead Isotopes to Geochemical Exploration of Gold Deposits in Baoban , Hainan Province, China

• Published in: Acta geochimica Vol. 22; no. 3; pp. 244 - 252
• Main Author: 常向阳 朱炳泉 俞受鋆 夏萍
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 2003; Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China%Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China%Department of Geosciences, Zhongshan University, Guangzhou 510275, China; Department of Environmental Sciences, Guangzhou University, Guangzhou 510405, China
• Subjects: Anomalies; Chemical composition; Composition; Deposits; Eigenvectors; Evaluation; Exploration; Fluids; Forecasting; Geochemistry; Gold; Isotope ratios; Isotopes; Lead; Lead isotopes; Lithosphere; Mineral deposits; Mineralization; Ores; Position measurement; 地球化学探测; 金矿床; 铅同位素; Hainan China; China; gold deposit; Hainan Province; geochemical exploration; lead isotope
• ISSN: 1000-9426; 2096-0956; 1993-0364; 2365-7499
• DOI: 10.1007/BF02842868

Lead isotopes have been widely applied in geochemical exploration and evaluation of ore deposits, as well as in ascertaining the age of mineralization and the source of ore fluids.Long-term practice showed that the method of lead isotope targeting is somewhat efficient for macroscopic evaluation of forecasting areas, but not powerful enough for for ecasting concealed orebodies. As the contents of U and the variation of U/Pb ratio sharply decrease with depth in the lithosphere, U-Th-Pb isotopic differentiation must have occurred during the crust-mantle e-volution. Lead isotopic ratios show a wide variation range, varying in the front of mineralizationand shallow-derived ores, but maintaining very stable in the major orebody and being usuallyclose to the average isotopic composition of the crust and mantle of the continent block fromwhich the ores were derived. Therefore, the lead isotopic composition can serve as a measure for identifying the position of mineralization. The lead isotope geochemistry was applied to the ex-ploration and evaluation of the Baoban gold deposits of Hainan Province, China. The an alyticalresults of ore veins and adjacent rocks showed that there is a correlation between the lead isotopedata and the position of orebody. Based on the experience from the Baoban gold deposits and other ore deposits in Yunnan Province, an exploration principle has been established, that is,positive anomalies of lead isotope eigenvectors for prospecting deep-seated orebodies and nega-tive anomalies of eigenvectors for enlarging lateral exploration surrounding the known deposit.The ore beds in the Erjia and Beiniu mining districts should be as signed to the deep part of the orebody and those in the Tuwaishan mining district should be the shallow part, so ore beds cor-responding to those in the Erjia and Beiniu mining districts may be found in the Tuwaishan min-ing district.