滇西新生代盆地与砂岩型铀矿成矿

The Cenozoic Basins and Sandstone-type Uranium Mineralization in Western Yunnan

滇西新生代盆地内蕴藏着丰富的铀资源,现已探明8个中、小型砂岩型铀矿床,是中国重要的砂岩型铀矿成矿带之一。本文在收集研究前人施工钻孔资料1200个,施工钻孔25个的基础上,编制岩性—岩相—地球化学剖面图66张,研究了滇西新生代盆地与砂岩型铀矿成矿。认为滇西地区存在2种类型的新生代盆地,其盆地沉积演化、火山活动、地貌景观等不同,砂岩型铀矿成矿条件亦存在差异,成矿的专属性体现在于盆地的差异性。砂岩型铀矿成矿最有利的是北部腾冲地区找矿目的层上覆地层发育了区域性隔水层、存在火山活动、深切割低山—丘陵—河谷阶地地貌的新生代盆地。

There contained abundant uranium resources in the Cenozoic basins, western Yunnan,where 8 small-sized or medium-sized sandstone-type uranium deposits have been prospected ,and which is one of the important belts of sandstone-type uranium mineralization in China. Having collected and studied the data from 1200 drills, constructed 25 drills, writers drew up 66 rock-lithofacies-geochemical profiles, and studied the relations between the Cenozoic basins and sandstone-type uranium mineralization. It is considered that there exists two sorts of Cenozoic basins,they are different on sedimentary evolution ,volcanic activity and geographic view etc. , the metallogenic conditions of sandstone-type uranium deposits are also different. The advantaged basins for prospecting sandstone-type uranium deposits are those basins that developed regional isolatable water layer over the prospecting target layers, existed volcanic activity and deep incised landscape of low mountain-hill-river valley terraces in northern Tengchong area.