成都理工大学学报（自然科学版）2025，Vol.52Issue(4)：270-284,15.DOI:10.12474/cdlgzrkx.2024010403
滇东南文山州小洞锑矿床成因:来自硅质岩、辉锑矿元素及硫同位素的证据
Genesis of the Xiaodong Sb deposit,Wenshan Prefecture,southeast Yunnan:Constraints from geochemistry and S isotopes in siliceous rock and stibnite
摘要
Abstract
The Xiaodong Sb deposit in Wenshan Prefecture,Yunnan Province,is located in the southeastern Yunnan Sb metallogenic belt.The Sb ore body is present in siliceous rocks located in the lower section of the Tianpeng Formation,Middle Cambrian.Although previous studies proposed that it is a hydrothermal sedimentary Sb deposit formed via metamorphism,its petrogenesis and metallogenic mechanisms still remain unclear.This study performs major and trace element analysis of the siliceous rocks,and the results show w(SiO2)content of 84.70%～97.11%(average of 92.19%),while the w(Al2O3)has a content of 0.63%～6.08%(average of 3.56%).ΣREE ranges from 20.43×10-6 to 77.54×10-6,showing an enrichment of LREE and a depletion of HREE,with δEu(0.66～1.57)and δCe(0.95～1.15).The results reveal that the siliceous rocks formed by non-hydrothermal sedimentation in the continental margin and they originated in terrestrial sources.An LA-ICP-MS analysis of trace elements in the stibnite shows that the main substitution mechanism is 2Sb3+↔As3++(Cu++Pb2+).The δ34S value of stibnite(0.42‰to 4.91‰)shows the signature of magmatic sulfur,implying that the mineralized hydrothermal fluids maybe related to the Laojunshan intrusion or deep,hidden magmatic rocks.The comprehensive analysis presented here shows that the Xiaodong deposit is not related to hydrothermal sedimentation;instead,the mineralized material mainly came from magmatic hydrothermal fluid,which enriched the interlayer fracture belt during a late stage of magmatic activity.This study characterizes the deposit as a fault-controlled hydrothermal Sb deposit.关键词
硅质岩/辉锑矿/硫同位素/矿床成因/滇东南Key words
siliceous rock/stibnite/S isotope/ore genesis/southeastern Yunnan分类
地质学引用本文复制引用
林心怡,林木森,吴久芳,易友根,徐楷,徐净..滇东南文山州小洞锑矿床成因:来自硅质岩、辉锑矿元素及硫同位素的证据[J].成都理工大学学报（自然科学版）,2025,52(4):270-284,15.基金项目
国家自然科学基金重点项目(42230807) （42230807）
福建省教育厅2021年度中青年教师教育科研项目(JAT210031). （JAT210031）
