WU Lin1,2,3, HUANG Zhi-long1, WANG Zhi-lin4, WANG Yu-fei4, CHEN Jian5*, WU Tao1,2
(1. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China;
3. Laboratory of Coal Geology Bureau of Guizhou Province, Guiyang 550009, China;
4. Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring (Central South University), Ministry of Education, School of Geosciences and Info-Physics, Central South University, Changsha 410083, China；
5. The Sixth Geological Team, Guizhou Province Bureau of Nonferrous Metals and Nuclear Industry Geological Exploration, Kaili 556000, China)
Abstract: The Maochang bauxite deposit is located in the Xiuwen－Qingzhen area, central Guizhou Province. The ore body lies in the Lower Carboniferous Jiujialu Formation, under the dolomite of the Lower Carboniferous Baizuo Formation, and above the dolomite of the Middle-Upper Cambrian Loushanguan Formation. The genetic type of the deposit is an ancient weathering crust depositional type. The geochemical characteristics of major elements, trace elements and rare earth elements in bauxite, bauxitic clay and dolomite were studied. The results show that the bauxite is mainly composed of Al2O3, SiO2, Fe2O3 and TiO2, whereas the ore-bearing rock series are rich in trace elements such as Li, V, Ga, Sc, Nb, Ta, Th, Hf, Zr, Y and rare earth elements. The content and ratios of sensitive elements (Th, Sr/Ba, Th/U) indicate that the Maochang bauxite deposit was mainly formed in a land-sea interactive setting dominated by continental sedimentary setting, and the ore-forming process was mainly an alternating redox setting. The correlation of stable elements (Al2O3/TiO2, Al2O3/Zr, TiO2/Nb, Zr/Nb, Zr/Ta, Zr/Hf and Ta/Nb) and the chondrite-normalized REE pattern were used to discuss that the materials of ore-forming could be sourced from the dolomite of the Middle-Upper Cambrian Loushanguan Formation.
Keywords: bauxite; geochemistry; ore-forming materials; Maochang; Guizhou
ACTA MINERALOGICA SINICA Vol. 41, No.4/5, 2021, page 475-484
