DENG Hong 1, HUANG Zhi-long2, XIAO Xian-guo3, DING Wei2
(1. The 935 Team of Guangzhou Bureau of Nonferrous Geological Exploration, Huizhou 516001, China;
2. The State Key Laboratory of Ore Deposit Geochemistry, Chinese Academy of Science, Guiyang 550002, China;
3. Guizhou Province Bureau of Nonferrous Metals and Nuclear Industry Geological Exploration, Kaili 556000, China)
Abstract: Banpo antimony deposit is the only large antimony deposit in Metallogenic Belt of Antimony in South China. There has long been debated about the source of ore-forming fluid for this deposit, which seriously restricts the establishment of the genetic and prospecting model of the deposit. In this paper, we report REE concentrations of gangue calcites, host rocks and strata of different ages to discuss the source and evaluation process of ore-forming fluid. The results show that the REE compositions of gangue calcites with different occurrences are relatively homogeneous, exhibiting depleted LREE, enriched HREE, and MREE (Sm－Ho)-enrichment patterns, indicating that the ore-forming fluid were generated from the same source but underwent different evolutionary stages. REE contents are high in the gangue calcites, however, the gangue calcites show similar REE distribution pattern and relevant parameters with the leachate of carbonate and sedimentary rocks, a variety of evidences demonstrating that the ore-forming fluids are of the crustal type. However, the possible involvement of mantle fluids in the ore-forming processes cannot be ruled out. In addition, the study of REE in the gangue calcites can not only show constraints of the ore-forming process from region large-scale fluids migration but also provide an important ore prospecting indicator.
Key words: gangue calcite; REE geochemistry; ore-forming fluid; Banpo antimony deposit; Guizhou Province; China
ACTA MINERALOGICA SINICA Vol. 34, No. 2, 2014, Page 208-216
