江西虎家尖银金矿床地质及成因探讨  

GEOLOGICAL CHARACTERISTICS AND GENESIS OF THE HUJIAJIAN SILVER-GOLD DEPOSIT IN WANNIAN COUNTY,JIANGXI PROVINCE

作　　者：徐磊明 白鸽 何全泊 

机构地区：[1]地矿部矿床地质研究所 [2]江西局赣东北地质大队

出　　处：《矿床地质》1993年第2期138-147,共10页Mineral Deposits

摘　　要：该矿矿体受北东向断裂构造控制,容矿岩石为中元古界双桥山群的一套浅变质的火山-沉积岩。矿区内岩浆活动较弱。矿体呈单一脉状,矿石成分复杂,银矿物种类多(30余种),分属S-Sb-Cu-Ag及S-Sb-Pb-Ag两大系列。矿床的Sr、Pb、S、C、O、H同位素组成及矿石和容矿岩石的稀土配分表明成矿物质及成矿水溶液均主要源于基底构造层——中元古界双桥山群。该矿属中低温变质热液型银矿床。The Hujiajian silver-gold deposit is situated at the connection between the Pingxiang-Leping depression and the Guangmaoshan anteclise. Its orebo- dies are controlled by NE-trending faulted structures, and its host rocks are volcano-sedimentary rocks of the Middle Proterozoic Shuangqiaoshan Group. Intrusive activity is weak, with merely small intermediate-basic pre-ore dikes observed in the ore district. The orebodies take the veinlike form, and the ore composition is complex. There are many (more than 30 kinds) of silver minerals, belonging to S-Sb-Cu-Ag and S-Sb-Pb-Ag series. The ore-forming process could be divided into two phases: hydrothermal filling phase and supergene oxidation phase. The former phase includes four mineralization stages, namely quartz-carbonate stage, quartz-sulfide stage with silver minerals deposited at the end, carbonate stage and silver sulfosalt stage. Wall rock alterations are silicification and carbonatization. The upper limit of the mineralization age(the single stage Pb model age) of the deposit is 497.9940 Ma (pyrite) and 499.7953 Ma (galena). Isotope compositions are as follows: ^(87)Sr/^(86)Sr=0.71483±0.00013 and 0.71403±0.00009 (rhodochrosite); ^(206)Pb/^(204)Pb=17.937 and 17.920,^(207)Pb/^(204)Pb=15.594 and 15.582, ^(208)Pb/^(204)Pb=38.314 and 38.271 (galena and pyrite respectively); δ^(34)S‰(CTD)=-0.6～+3.3(sulfides);δ^(13)C％(PDB)=-6.1～-8.0(carbonate);δ^(18)O‰(SMOW)=+15.8～+18.7 (carbonate); δD‰ (SMOW)=-74.4 (dolomite) and-58.7 (quartz). The REE content of the ore varies from 9.61 to 20.56×10^(-6), and the REE content of the host rock is between 154.27 and 194.75×10^(-6). The strontium, lead, sulfur, carbon, oxygen, hydrogen isotope compositions and the chondrite-normalized REE patterns of the ore and host rocks suggest that both the ore-forming substance and the mineralizing solution came from the basal Middle Proterozoic Shuangqiaoshan Group. The Hujiajian silver-gold deposit seems to be a metamorphogenic mesothermal-epithermal filling-m

关 键 词：银矿床 金矿床 地质 成因 同位素 

分 类 号：P618.502[天文地球—矿床学]