沉积盆地水文地质与砂岩型铀矿成矿关系--以松辽盆地开鲁坳陷砂岩型铀矿为例  

Relationship Between Hydrogeology and Sandstone Uranium Mineralization in Sedimentary Basin:A Case Study of Sandstone Uranium Survey in the Kailu Depression of the Songliao Basin

作　　者：陈振岩[1] 满安静 陈星州 熊耀华 邵建欣 王雷 孙平 CHEN Zhenyan;MAN Anjing;CHEN Xingzhou;XIONG Yaohua;SHAO Jianxin;WANG Lei;SUN Ping(New Energy Development Branch of Liaohe Petroleum Exploration Bureau,Panjin 124010,Liaoning,China;Exploraion and Development Institute of Liaohe Oilfield,Panjin 124010,Liaoning,China)

机构地区：[1]辽河石油勘探局新能源开发分公司,辽宁盘锦124010 [2]辽河油田勘探开发研究院,辽宁盘锦124010

出　　处：《大地构造与成矿学》2021年第6期1174-1184,共11页Geotectonica et Metallogenia

基　　金：国家重点研发计划“深地资源勘查开采”重点专项(2018YFC0604200)子课题“北方砂岩型铀能源矿产基地深部探测技术示范”(2018YFC0604205)资助。

摘　　要：地层水是含矿溶液、成矿元素迁移的动力和载体。因此,水文地质作用在砂岩型铀矿成矿过程中扮演着重要角色。地层水的分带性及其化学特征的一系列变化从一个侧面反映砂岩型铀矿成矿的可能性。本文以松辽盆地开鲁坳陷砂岩型铀矿为例,从盆地地层水分带性及其特征分析入手,剖析了地层水分带性与氧化‒还原演变特征,论述了水文地质条件与铀迁移的关系,揭示了铀成矿完整的地球化学环境演变序列。浅部序列完整指示砂岩型铀矿的有利富集区,深部氧化带(水交替强烈带)缺失不利于铀成矿。以此为基础,提出古构造的缓坡及沟槽是铀成矿的有利区带,氧化带预富集铀是“汇”区潜在的重要源,成矿期氧化带规模对铀矿床大小具有重要影响。上述认识成功指导了松辽盆地开鲁坳陷砂岩型铀矿的勘查。Formation water is an important type of ore-bearing solution and a powerful carrier of ore-forming elements.Hydrogeology plays an indispensable role in the process of sandstone uranium mineralization.Therefore,the hydrochemical changes of groundwater can reflect the possibility of sandstone uranium mineralization.Taking the sandstone uranium deposit in the Kailu depression of the Songliao basin as an example,this paper analyzes formation water zonation and oxidation-reduction evolution characteristics,discusses the relationship between hydrogeological conditions and uranium migration,and reveals the complete sequence of geochemical evolution of uranium mineralization.The completeness of shallow sequences is favorable for sandstone uranium deposit,whereas the absence of deep oxidation zone is unfavorable for uranium mineralization.On this basis,it is proposed that the gentle slope and groove of the paleostructure are favorable zones for uranium mineralization;pre-enrichment of uranium in oxidation zone is an important source in the“catchment”zone;and the scale of oxidation zone in mineralization period affects significantly the size of the uranium deposits.The above understandings have successfully guided the exploration of sandstone uranium deposits in the Kailu depression of the Songliao basin.

关 键 词：开鲁坳陷 钱家店铀矿 沉积盆地 水文地质 砂岩型铀矿 沟槽 

分 类 号：P619.1[天文地球—矿床学]