中文摘要:作者通过对黑区_雪区矿床深入的野外考察、典型矿石组构的显微鉴定、矿石化学成分测试研究后认为，与区域内广泛分布的MVT型矿床相对比，黑区_雪区矿床存在诸多明显不同的特征，主要为：①铅锌矿化与灯影组巨厚的白云岩顶部所夹的富含有机质的黑色微晶硅质岩及同生角砾岩层密切相关；②矿体呈层状与容矿围岩整合接触，延伸规模巨大，地表露头断续长6 km以上；③矿石内发育层状、纹层状、条纹_条带状、同沉积角砾状、同沉积滑动变形等沉积构造；④闪锌矿、黄铁矿等金属硫化物以及含矿硅质岩的粒度微细，80%的粒径介于0.001～0.5 mm之间；⑤围岩蚀变微弱或不发育；⑥含矿层状微晶硅质岩的形成温度低(80～86℃)。作者认为，黑区_雪区层状整合铅锌矿床属于典型的海底热水沉积成因(SEDEX型)，是川滇黔铅锌矿集区内新发现的具有重要找矿前景的矿床类型。热水喷流_沉积成矿作用与灯影晚期在碳酸盐台地内发育的近东西向汉源_峨眉次级凹陷以及位于该凹陷中心的同生断裂带的活动有内在联系。
Abstract:Numerous Pb_Zn deposits hosted in Upper Sinian_Lower Paleozoic_Upper Paleozoic carbonate strata were discovered in the last half century along the well-known Pb-Zn ore belt in the Sichuan_Yunnan_Guizhou border area, tectonically the western margin of the Yangtze craton. With typical epigenetic characteristics, these deposits are commonly classified as MVT-type deposits.Within the ore belt, the Heiqu-Xuequ deposit, a super-large (2.6 million tonnage of Pb-Zn) stratiform Pb_Zn deposit, was discovered in Hanyuan, Sichuan, in early 1990s and has been mined over ten years. It is conformably hosted at the dolomite top of the Upper Sinian-Lower Cambrian Dengying Formation. Based on detailed field and microscope observation as well as geochemical analysis of the ores, the author holds that geological and geochemical characteristics of the deposit are significantly different from those of the MVT-type deposits in the Pb-Zn ore belt in that ① Pb-Zn mineralization is spatially confined to the intercalated blackish microcrystal silicalite rich in organic materials and brecciated dolomite at the top of the Dengying Formation, ② the outcrop of the stratiform orebodies extends over 6000m, ③ typical sedimentary fabrics, such as stratiform, laminated, banded, synsedimentary brecciated, and interbedded softly folded structures, are well developed, ④ the mineral grain sizes of sphalerite, pyrite, dolomite, and quartz in the ore are very fine, 80% statistically ranging from 0.001 to 0.5mm, ⑤ alteration is very weak or not developed, and ⑥ the ore_bearing silicalite was formed at low temperature (80～86℃). The deposit is considered to be genetically of the SEDEX-type, a new type with large Pb-Zn resource potential in the ore belt. The hydrothermal activities and Pb-Zn mineralization were probably related to the development of the EW-stretching Hangyuan-Emei subdepression within the carbonate terrace and the activities of the contemporaneous faults in the middle of the depression during the Upper Sinian-Lower Cambrian Dengying period.
文章编号：
中图分类号：
文献标志码：
基金项目:国家973项目(2002CD412609)
引用文本：
林方成.2005.四川汉源黑区_雪区层状铅锌矿床典型矿石组构与成因[J].矿床地质,24(2):122~133.2005.Typical ore fabrics of Heiqu_Xuequ stratiform lead_zinc deposit in Hanyuan, Sichuan, and their genetic implications[J].Mineral Deposits24(2):122~133
图/表
