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利用电子探针以及扫描电镜和能谱仪相结合的方法对西南印度洋中脊表层沉积物进行了矿物学研究,结果表明:该区沉积物中含有黄铁矿、闪锌矿、黄铜矿以及等轴方黄铜矿等硫化物颗粒,硫化物颗粒多呈自形-半自形,保存完好。其中黄铁矿晶体呈立方体及立方体-八面体聚形形态,闪锌矿与黄铜矿晶体中常见溶蚀孔洞,而等轴方黄铜矿中出现固溶体分解结构。硫化物类型、颗粒结构和微量元素组成指示49.6°E热液区附近沉积物中的硫化物至少属于两个热液成矿阶段的产物,早期为中温成矿阶段,后期经历了高温富Fe流体的改造;50.5°E热液区附近沉积物中出现了高温硫化物组合。
The mineralogical study of the surface sediments in the southwestern Indian Ocean Ridge was carried out by means of the combination of electron probe, SEM and EDS. The results show that the sediments of this area contain pyrite, sphalerite, chalcopyrite and Isotopic chalcopyrite and other sulfide particles, sulfide particles mostly self-shaped - semi-self-shaped, well preserved. Among them, the pyrite crystals are cube and cube-octahedron polygons, common dissolution holes are found in the sphalerite and chalcopyrite crystals, and the solid solution decomposition structure appears in the equiaxed chalcopyrite. Sulfide type, grain structure and trace element composition indicate that the sulfide in the sediments near the 49.6 ° E hydrothermal zone belongs to at least two hydrothermal mineralization stages, the early stage is the mid-temperature mineralization stage, and the latter experienced high-temperature Fe-rich fluid The high-temperature sulphide assemblage occurred in the sediments near the hydrothermal zone of 50.5 ° E.