砂岩型铀矿的两种成矿模式:泾川式和塔勒式  

Two Metallogenic Models of Sedimentary-Hosted Uranium Deposit: Jingchuan and Tale Types

作　　者：程银行 金若时 苗培森 王少轶[1,2] 滕雪明 Cheng Yinhang;Jin Ruoshi;Miao Peisen;Wang Shaoyi;Teng Xueming(Tianjin Center,China Geological Survey(North China Center for Geoscience Innovation),Tianjin 300170,China;Key Laboratory of Uranium Geology,China Geological Survey,Tianjin 300170,China)

机构地区：[1]中国地质调查局天津地质调查中心(华北地质科技创新中心),天津300170 [2]中国地质调查局铀矿地质重点实验室,天津300170

出　　处：《地球科学》2025年第1期46-57,共12页Earth Science

基　　金：国家重点研发计划项目(Nos.2023YFC2906700,2018YFC0604200);自然资源部青年人才项目(No.自然资科技函[2022]129号);中国地质调查局地质调查项目(Nos.DD20240116,DD20230027,DD20221678,DD20190813);国家自然科学基金重点支持项目(No.92162212);国家重点基础研究发展计划(973计划)项目(No.2015CB453000);国际地球科学计划项目(No.IGCP675)。

摘　　要：目前砂岩型铀矿成矿模式种类较复杂.试图从还原介质内生和外生两个角度,分析鄂尔多斯盆地泾川油气田区和塔然高勒煤田区两个特大型铀矿床的成矿条件、矿物特征、地球化学特征等,建立泾川式和塔勒式两种铀成矿模式.泾川式还原介质以烃类流体为主,为沉积成岩期后下伏烃源岩排出运移至下白垩统洛河组,与表生含氧含铀流体耦合成矿,矿体受岩层渗透性、后期断裂构造和水系展布等要素控制明显,具有矿化层多的特征,常发育十几层,受烃类流体运移影响,横向变化较大,常切穿层理;铀矿物从几微米至十几微米,分布较为均匀.塔勒式还原介质以煤屑等为主,为同沉积成岩期碎屑,近于顺层产出,矿体横向展布稳定,与地层基本一致;铀矿物颗粒大小变化大,从几微米至几百微米,分布不均匀.该认识为盆地多能源成矿响应和铀矿成矿机理研究再突破提供了新方向.The existing ore-forming models related to sedimentary-hosted uranium deposits have been primarily established focusing on different ore-controlling factors such as tectonics,sedimentation,and fluids.These models are diverse and complex.Over the past decades,with the comprehensive development of secondary exploration for uranium in drilling data from coalfields and oilfields,the close spatial coexistence pattern of"coal-oil-uranium"has been rapidly revealed.This paper analyzes the reducing media that constrain the enrichment of sedimentary-hosted uranium deposits from different perspectives.By systematically comparing and analyzing the ore-forming conditions,mineral characteristics,and geochemical features of the super large uranium deposits in the Jingchuan oil and gas field and the Tale coalfield in the Ordos Basin,two uranium ore-forming models,namely the Jingchuan type and the Tale type,are established.The Jingchuan type reducing media are primarily hydrocarbon fluids(such as CH4,H2,CO,as well as secondary H2S,pyrite,etc.),which are mainly derived from the expulsion and migration of deep-seated hydrocarbon source rocks after the sedimentary diagenesis period to the Lower Cretaceous Luohe Formation,coupled with the ore-forming process of surface oxygenated and uranium-bearing fluids.The ore bodies in this model are notably controlled by factors such as reservoir permeability,late-stage fault structures,and hydrological distribution,often characterized by the presence of multiple mineralized layers,typically dozens or even scores of layers.Constrained by the migration range of oil and gas,they exhibit significant lateral variations and phenomena of ore bodies cutting across bedding planes.The uranium minerals are primarily asphaltic uranium ores,appearing as emulsion texture,angular texture,vein-like texture,with relatively small grains ranging from a few to tens of micrometers,occasionally reaching several tens of micrometers,and distributed relatively evenly,accompanied by minerals such as pyrite,quartz,calci

关 键 词：砂岩型铀矿 泾川式 塔勒式 成矿模式 还原介质 矿床学 

分 类 号：P619.14[天文地球—矿床学]