摘要
白面石地区有着得天独厚的铀成矿地质背景,经1960—1980年代勘查,曾提交了白面石大型铀矿田,成为了我国重要的铀资源基地。该区的铀矿化主要赋存在中侏罗世白面石火山盆地盖层底部的砂岩中,前人将其成因类型定为沉积砂岩型铀矿床,从此结束了该区的铀矿找矿工作。因此,30多年来,该区的铀矿成因及其发展潜力成为了众多铀矿工作者的研究课题。近年来,作者在重新整理该区资料的基础上,广泛搜集了矿田内同位素定年最新成果,认为:白面石铀矿田是在富铀基底花岗岩的风化,使铀活化迁移形成高铀砂岩层,是成矿的基础;到中侏罗世在盆地内砂岩沉积的同时,发生了双峰式火山岩喷溢,玄武岩覆盖在高铀砂岩层之上,起着热盖和封闭作用,使铀聚积成矿,是成矿的关键;后期的次火山岩的侵入,带来的热源,再次使铀活化加富了脉岩两侧砂岩中铀的矿化。为此,其成因类型应为成岩成矿,火山热盖,脉岩迭加的火山热盖亚型铀矿。显然,白面石地区还有极大的找矿潜力,今后的找矿方向不仅是在残留盆地砂岩的铀矿,尤其是要寻找盆地基底花岗岩中和火山机构中的富矿。
Baimianshi District has its distinct uranium metallogenetic geological setting.During 1960-1980 period,it has submitted the Baimianshi large uranium ore field and became one of Chinas important uranium resource bases.Uranium mineralization of this district mainly distributes in the sandstone cap layer on the bottom of the Middle Jurassic Baimianshi volcanic basin.People set the genetic type as sedimentary sandstone-type uranium deposit,which lead to end of prospecting work of the uranium deposits.Therefore,for more than 30 years,uranium mineralization and development potential in this district has become the research topic for many uranium geological workers.In recent years,the author reorganizes the data,broadly collecting the latest achievements on orefield isotopic dating.And the Baimianshi uranium orefield is the weathering of the granite uranium rich basement,and the uranium activation and migration form high uranium metallogenesis sand,which are the foundation of the mineralization; sandstone sedimented in the basin in the Middle Jurassic,and in the meantime the Shuangfeng Type volcanics eruption happened,basalt covering the high uranium sandstone layer,acting as a thermal cover and sealing role,making the accumulation of uranium metallogenic mineralization,which is the key of the mineralization; the heat caused by the invading subvolcanic rock in the anaphase,once again make uranium mobilization and rich vein rocks on both sides of the sandstone uranium mineralization.Therefore,the genetic type should be mineralization,volcano thermal covering,heat Gaia type uranium veins superposition.Obviously,the Baimianshi district has great exploration potential.And the prospecting direction in the future is not only the uranium deposits in the residual basin sandstone,but also the rich ore in the basin basement granite and volcano mechanism.
出处
《东华理工大学学报（自然科学版）》
CAS
2014年第2期122-128,共7页
Journal of East China University of Technology(Natural Science)
关键词
白面石
火山盆地
成因类型
热盖
资源潜力
Baimianshi
volcano basin
genetic types
thermal cover
resource potential
