ZHANG Feng-lei1，JI Hong-bing1,2,*，WEI Xiao1，LI Dao-jing1
（1.The State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China;
2.Resource, Environment and GIS Key Laboratory of Beijing City, Department of Geography, Capital Normal University, Beijing 100037, China）
Abstract: This paper studied the transportation and distribution characteristics of trace elements under weathering and also discussed the origin of red weathering crust overlying carbonate. We selected a well-developed profile of primary dolomite at Xinpu Town, Zunyi, Guizhou Province, as the study object. Zr was treated as an immobile element. The following conclusions are drawn: 1) This dolomite weathering profile we studied is a weathering-leaching profile. And the distribution and transfer coefficient of trace elements changes regularly in the carbonate section. The strong correlations between Nb-Ta, Zr-Hf and Y-Yb prove that this profile is a protogenesis profile. 2) Most trace elements show enrichment during the leaching process, especially maximization at the rock-soil interface. Nb,V and Hf are immobile elements. 3) The mass transfer coefficient is obviously different between LREE and HREE. The mass transfer coefficient of LREE is higher than that of HREE at the rock-soil interface. Element migration is also influenced by ferricrete. In all, this research result has meaningful denotation to discuss the origin of red weathering crust in karst areas.
Key words: trace element; dolomite；weathering profile; mass transfer coefficient; Guizhou
EARTH AND ENVIRONMENT Vol. 42, No.5, Tot No.301, 2014, Page 611-619
