Pb Isotopic Compositions and Material Sources for Dolomite Weathering Profile in Central Guizhou
详细信息
- 责任者：Ji Hongbing (Key Laoratory of Environmental Rources ; GIS ; College of Resource Environment and Tourism ; Capital Normal University ; Beijing 100048 ; China) ; Wang Shijie
- 刊名：Geological Review
- 出版年：2011
- 卷期：57(1)
- 关键词：白云岩 ; dolostone ; 铅同位素 ; lead isotopes ; 物源区 ; provenance ; 风化壳 ; weathering crust ; 贵州 ; Guizhou Province
- 页码：p.109-117
- 图表：5 illus., 1 table, 66 refs.
- 分类号：0803
- issnNo：ISSN0371-5736
- isbnNo：CN11-1952/P
摘要
It is a disputed question for forming and evolution of red residua on the surface of carbonate rocks,particular for their material sources. The authors have conducted a comprehensive analysis of Pb isotopes for the Pingba profile in Centrial Guizhou Province. The Pb isotopic composition of the whole-rock samples showed that the lead is dominated by feldspar mineral-derived "common lead", with n(206Pb)/n(204Pb) being about 19.29 and 19.04~20.56 for dolomite and soil samples, respectively, greatly different from the Pb isotopic composition of the average continent, China’s regional anthrogenic background,and aerosols. The data points of samples for n(208Pb)—n(206Pb) and n(207Pb)—n(206Pb) isotopic spaces analysis all fall on a better mixing array, showing the mixing of carbonate rocks and siliceous components and indicating that the Pingba profile is the result of chemical weathering.