中国北方中新生代盆地深部砂岩铀矿成矿条件与找矿方向  

Metallogenic condition and prospecting orientation for deep sandstone-hosted uranium deposits in Mesozoic-Cenozoic basins of North China

作　　者：苗培森[1,2] 李建国 汤超[1] 金若时 程银行 赵龙[1,3] 肖鹏 魏佳林[1] 

机构地区：[1]中国地质调查局天津地质调查中心,天津300170 [2]中国地质调查局天津地质调查中心非化石能源矿产实验室,天津300170 [3]中国科学院地质与地球物理研究所,北京100029

出　　处：《地质通报》2017年第10期1830-1840,共11页Geological Bulletin of China

基　　金：国家重点基础研究发展计划(973计划)<中国北方巨型砂岩铀成矿带陆相盆地沉积环境与大规模成矿作用>(编号:2015CB453000);中国地质调查局项目<油气田勘查区砂岩型铀矿调查与勘查示范>(编号:DD20160128)

摘　　要：受开采技术、成本和成矿理论制约,现有的砂岩型铀矿勘查主要选择在盆地边缘700m以浅的地区,对盆地深部的铀矿找矿潜力研究较少。总结中国北方重要中新生代盆地的含铀岩系、构造特征,结合近年开展的北方砂岩型铀矿深部找矿,分析了盆地深部成矿有利的沉积建造、构造与流体改造、还原条件等,指明了盆地的深部找矿潜力。同时指出,作为战略储备,当前盆地深部寻找砂岩型铀矿要优先重视2个方向:(1)在盆地边缘斜坡区,重点以发育红-黑岩系结构的含铀地层为目标,寻找与浅部成矿条件相似的深部矿床;(2)在盆地中心区,以含铀的红色岩系为重点,优先寻找延伸至盆地深部的正向构造区和砂体发育区。这些认识在松辽盆地的铀矿调查中得到验证。The exploration of sandstone-hosted uranium deposits has only been focused on the basin margins with the depth less than 700 m because of restrictions of mining technology, cost and metallogenic theory. The prospecting potentiality of deep uranium deposits in basins has always been ignored. In this study, favorable sedimentary structure, tectonic movement, geological fluid and reduction condition of deep sandstone-hosted uranium deposits were discussed based on the summary of tectonic settings and uranium-bearing strata of known shallow sandstone-hosted uranium deposits in Mesozoic-Cenozoic basins in North China and new findings from the exploration of deep sandstone-hosted uranium deposits in recent years. Meanwhile, prospecting potentiality of deep sandstone-hosted uranium deposits was assessed and two directions were preferentially pointed out:(1) at the margin slope of the basin, the'red and black'strata series should be preferentially targeted in search for the potential deep deposits whose formation conditions are similar to the conditions of the shallow deposits;(2) at the center of the basin, emphasis should be put on the red layer with positive structure and sand body developed areas in the deep buried basin. These suggestions have been proved to be effective in the uranium investigation in Songliao basin.

关 键 词：砂岩型铀矿 深部找矿 成矿条件 找矿方向 中新生代 陆相盆地 

分 类 号：P534.5[天文地球—古生物学与地层学] P534.6[天文地球—地质学]