福建尤溪梅仙矿床闪锌矿中黄铜矿交生体的交代成因  

The Replacement Origin of "Chalcopyrite Disease" in Sphalerite in the Meixian Deposit, Youxi County, Fujian

作　　者：周兵[1] 顾连兴[1] 张文兰[1] 段芸[1] 

机构地区：[1]南京大学内生金属矿床国家重点实验室,210093

出　　处：《地质论评》1999年第1期15-18,T001,共5页Geological Review

基　　金：国家自然科学基金(编号49733120)

摘　　要：福建尤溪梅仙块状硫化物矿床中的闪锌矿经50％HNO_3浸蚀后发现,微米级的黄铜矿交生体呈乳滴状、棒条状、蠕虫状等沿闪锌矿解理面、双晶面和颗粒边界、裂隙等处分布,并且黄铜矿交生体所占体积均在5％以上,因此闪锌矿中有限的Cu的溶解度使出溶无法解释黄铜矿交生体的成因。交生体的结构特征及其与黄铜矿脉的关系暗示其可能是交代成因。而对横切黄铜矿乳滴的电子探针分析中铁含量特征的研究,证实梅仙矿区闪锌矿中的黄铜矿交生体系含Cu、Fe的热液交代所致。Sphalerite in the Late Proterozoic Meixian massive sulfide deposit, Youxi county, Fujian province, is heavily infected with the chalcopyrite disease. As revealed by etching in 50% HNO3, chalcopyrite viruses occur mostly as blebs, rods and worms several microns in size inside sphalerite grains and along cleavages and twin faces of sphalerite. Chalcopyrite viruses occupy more than 5% in volume of the sphalerite. Such a high density of viruses and hence the high con-tent of copper in sphalerite can not be explained in terms of chalcopyrite exsolution. Chalcopyrite viruses are seen, in some cases, connected with chalcopyrite veins and patches cutting and replac-ing diseased sphalerite in the same samples, inplying that the viruses should have been produced by replacement of the sphalerite. Electron microprobe analyses on two profiles across chalcopyrite blebs in sphalerite show that there is no Fe content decrease in the sphalerite in the close vicinity of the viruses, indicating that the fluid for the replacement has introduced Fe as well as Cu to the sphalerite.

关 键 词：闪锌矿 黄铜矿 交代作用 硫化物矿床 

分 类 号：P578.23[天文地球—矿物学] P578.292[天文地球—地质学]