摘要
为了研究二连盆地呼仁布其凹陷查干敖包地区赛汉组铀矿化特征及找矿方向,以煤田钻孔资料“二次开发利用”作为铀矿勘查新思路,运用“异常筛选与选区分析、原位验证与环境判别”的煤矿区铀矿地质调查模式,结合水成铀矿理论,对研究区收集的煤田钻孔测井成果展开综合研究。结果表明,在赛汉组中圈定出规模较大且连续的放射性异常,显示了较好的找矿前景。择优选择煤田潜在铀矿孔进行钻探验证,发现了具有工业意义的铀矿孔,且赛汉组上段主要发育两层铀矿化。进一步对研究区构造条件、铀源、岩相及地层条件、古气候与古水文条件及还原作用等分析,认为赛汉组沉积了一套冲积扇-扇三角洲-湖沼相的含煤碎屑建造,地层埋藏浅、砂体厚度适中,连续性较好,具备“泥-砂-泥”结构,炭屑和黄铁矿等有机质发育,具备铀成矿基本条件。赛汉组上部普遍发育潜水氧化作用,在扇三角洲前缘分流河道砂体的有利结构部位寻找潜水转层间氧化作用,是下一步找矿主攻方向。
To study the uranium mineralization feature and find the exploration direction in Saihan Formation of the Chagan'aobao area of the central of Hurenbuqi depression,raw borehole data and the logging outcome in coalfield were collected with the idea of“screening abnormal for prospect analysis and in-situ verification for environmental discrimination”guided by the theory of hydrogenesis.the comprehensive research delineated a large and continuous radioactive anomaly with good prospecting potential.Some bore hole in the anomaly area was selected for the verification and two economical mineralization layer was discovered in the upper member of Saihan Formation.Further research on the tectonic conditions,uranium sources,lithofacies and stratigraphic combination,the paleo climate,paleo hydrology condition and reducing action,suggested that a set of coal bearing clastic formation was deposited in the alluvial fan-fan delta-lacustrine environment.The formation was shallow buried and developed mudstone-sandstone-mudstone layers and the sand body is of moderate thickness,good in continuity and rich in carbon debris and pyrite.Phreatic oxidation is commonly developed in the upper member of Saihan Formation and change to interlay oxidation in the sand body of the distributary channel in the front of fan-delta,where is the target area for next exploration.
作者
赵天林
魏安军
田亮
尹永朋
ZHAO Tianlin;WEI Anjun;TIAN Liang;YIN Yongpeng(Sino Shaanxi Nuclear Industry Group Geological Survey Company Ltd.,Xi'an,Shaanxi 710100,China)
出处
《铀矿地质》
CAS
CSCD
2021年第5期854-868,共15页
Uranium Geology
基金
中国地质调查局天津地质调查中心项目“煤田勘查区砂岩型铀矿调查与勘查示范”(编号:DD20160127-29)资助。
关键词
砂岩型铀矿化
赛汉组
找矿方向
查干敖包地区
二连盆地
sandstone-type uranium
Saihan Formation
prospecting direction
Chagan'aobao area
Erlian Basin
