新疆天山成矿带沉积磷矿床地质及地球化学研究

Geology and Geochemistry of Sedimentary Phosphate Beds at Mount Tianshan Metallogenic Belt in Xinjiang Uygur Autonomous Region

采用对不同聚磷区含磷岩系剖面进行对比,并对不同类型矿石分别采样进行地球化学测试,系统研究了天山成矿带内的沉积磷矿,将该区含磷岩系划分为碎屑含磷岩系、黑色含磷岩系以及火山-硅质含磷岩系。根据研究区含磷岩系特征,划分出碎屑岩型、黑色碳质岩型和火山-硅质岩型,并分别对3种类型磷矿的地球化学特征进行了研究。碎屑岩型磷矿以MgO含量明显偏低,Ba含量偏高,伴生Yb、La为特点;黑色碳质岩型磷矿以含V、U为特点;火山-硅质岩型磷矿Ba含量则明显偏低,Eu基本无异常,Ce亏损明显,以伴生Mo、Ni为特征。最后,根据成矿条件划分出乌什—柯坪、库鲁克塔格、科古琴和平台山—方山口4个远景聚磷区。

By using such methods as contrast of the sectional drawings of phosphoric rock series in different phosphorus enrichment areas and the geochemical test of samples collected from different types of phosphate beds,the paper studied the sedimentary phosphate beds at Mount Tianshan metallogenic belt systematically and divided the phosphoric rock series into clastic rock series,black carbonaceous rock series and volcano-silicolites phosphate rock series.According to the characteristics of phosphoric rock series,some subtypes of rocks have been divided and the geochemical and geological characteristics of three kinds of phosphate beds have been researched.The results showed that clastic-type phosphate beds were characterized by obviously lower content of MgO,higher content of Ba and accompanying Yb and La;black carbonaceous shale-type phosphate beds were characterized by containing V,U elements;volcano-silicolites-type phosphate beds were characterized by obviously lower content of Ba,no abnormality of Eu,obvious depletion of Ce and accompanying Mo and Ni.According to the metallogenic conditions,such four perspective phosphorus enrichment areas as Wushi-Keping,Kuruktag,Kokirqin and Pingtaishan-Fangshankou have been divided.