塔西南缘铅锌矿带典型矿床的矿石组构特征

Texture and Structure Characteristics of Ore from Typical Deposits of Lead-Zinc Ore Belt in the Southwestern Margin of Tarim

通过对位于西昆仑北带奥依塔格-库尔良晚古生代(弧后)裂陷盆地塔西南缘铅锌矿带典型矿床矿石结构构造特征进行研究,总结出该矿带各个矿床(点)之间具有相同或相似的矿物共生组合(黄铁矿-方铅矿-闪锌矿-黄铜矿)以及相似的组构特征。主要结构包括草莓状结构、骸晶结构、自形晶结构、固溶体分离结构、交代结构及揉皱结构等;构造包括浸染状构造、流动构造、条带状构造、脉状构造及角砾状构造等,这些组构特征的共性表明成矿作用均具有多期多阶段的特征,并指示出热水沉积成矿兼有后期热液改造的结构构造特征。结合野外地质特征,该区铅锌矿床形成经历了同生沉积与后期改造过程。

This paper reported texture and structure characteristics of typical deposits from the southwest margin of Tarim platform of lead-zinc ore belt which located at late-Paleozoic Oytage-kurliang fissure basin in the northern part of Western Kunlun Orogenic Belt. It was showed that research deposits have not only the same or similar mineral association（ eg： Pyrite-Galena-Sphalerite-Chalcopy-rite）, but also the similar characteristics of ore structures and textures. Texture of ore includes framboidal texture, myrmekitic texture, idiomorphic granular texture, ex-solution texture, metasomatic relict texture, crumpled texture, disseminated structure, flow structure, banded structure, vein structure, brecciated structure etc. Generality of these structure features indicates that mineralization has the characteristics of multistage, and demonstrates both syngenetic sedimentation structure characteristics and late-hydrothermal transformation structure characteristics. Combined with the field geological characteristics, it is proved that the lead and zinc ore deposits experienced syngenetic sedimentation and transformation process.