中文摘要:通过矿床地质、矿物包裹体及同位素地球化学研究确定庞西洞银矿受韧性-脆性剪切构造带控制,成矿与燕山期同熔型花岗岩有关。矿床围岩蚀变钾化,黄铁绢英岩化强烈。成矿流体K+>Ca2+>Na+>Mg2+;SO42->Cl->HCO3->F-;CO>>CO2>CH4。流体低盐度(2.2 wt%~4 wt%NaCl)、弱酸性(pH为4.6)、密度0.81。成矿温度270℃,压力700×105Pa,fO2=10-39~10-41,fS2=10-12~10-15,为中深中温岩浆热液银矿床。
这类矿床是我国银矿新类型,许多方面与焦家式破碎带蚀变岩型金矿成矿特征相似,在粤西、桂东极具远景。
Abstract:Based on geological, mineral inclusion and isotope geochemical studies, the authors hold that the Pangxidong silver deposit is controlled by a ductile-brittle shear structural zone with its mineralization related to Yanshanian syntectic granite. Wall rock alterations include intense K-feldspathization and pyrite phyllic alteration. The ore-forming fluids are characterized by K>Ca>Na>Mg, SO42->Cl->HCO3->F-, CO>>C02>CH4, low salinity(2.2 wt%-4 wt%NaCl), weak acidity (pH=4.6)and density 0.81. The ore-forming temperature is 270℃, pressure 700×105Pa, fO2 10-39~10-41 and fs2 10-12~10-15, indicating that the silver deposit is a mesothermal one. As a new type of silver deposit in China, this ore deposit bears strong resemblances to the Jiaojia gold deposit which also occurs in fracture zones and has been intensely altered. Gold prospects for this type of silver deposits exist in west Guangdong and east Guangxi.
文章编号:
中图分类号:
文献标志码:
引用文本:
王鹤年,杨建文,陈辉琪.1992.广东庞西洞银矿床的地球化学研究[J].矿床地质,11(2):179~187.1992.Geochemical Studies Of The Pangxidong Silver Deposit In Guangdong Province[J].Mineral Deposits11(2):179~187
图/表