Characteristics and Implication of Carbon and Oxygen Isotopes in Ga-Rich Manganese-Bearing Rock Series in Dongping, Guangxi
Li Qilai
Yi Haisheng
Xia Guoqing
Ji Changjun
Jin Feng
Abstract：Recently,an unusually high content of Ga was discovered in manganese carbonate deposits of the Beisi Formation in Dongping area,Guangxi.The content of Ga is between 5.16× 10-6 and 82.80× 10 6,and the average content is 33.76 × 10-6,which reaches the industrial grade of Ga.But,to date Ga is not extracted from manganese deposits.In order to deepen the understanding of this phenomenon,the results of carbon and oxygen isotopes in the Ga-rich manganese-bearing rock series are reported in this paper.The results show that δ1sCruB of ores and host rocks are-6.40‰0 to-2.20‰0 and-8.90‰0 to 0.90‰,respectively;δ18 OPDB of ores and host rocks are-9.00‰ to-7.90‰0 and-9.90‰0 to-3.90‰0,respectively.The results of the research show that (1) organic matter participates in the formation of manganese carbonate;(2) the Ga-rich manganesebearing rock series belong to hydrothermal sedimentary genesis,and the source of Ga is related to seafloor hydrothermal activity;(3) seafloor hydrothermal activity plays a key role in the mineralization process of this Ga-rich manganese-bearing rock series,it directly or indirectly provides a large amount of organic matter to formation of manganese carbonates,on the other hand,it brought a lot of Ga that can be adsorbed by manganese oxides or hydroxide,marine organisms (mostly hydrothermal microorganism),then Ga concentrated in manganese-bearing rock series by complex diagenesis and mineralization.
Keywords：manganese depositGa anomalycarbon and oxygen isotopesore deposits
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 1508-1518 )