辽东古元古代热液铀矿床形成的大地构造背景  

Tectonic Settings of Paleoproterozoic Hydrothermal Uranium Deposits in Eastern Liaoning Province, China

作　　者：郭春影[1,2] 韩军 徐浩[3] 白芸 任忠宝 韩愉[4] 赵宇霆 GUO Chunying;HAN Jun;XU Hao;BAI Yun;REN Zhongbao;HAN Yu;ZHAO Yuting(CNNC Beijing Research Institute of Uranium Geology,Beijing 100029,China;CNNC Key Laboratory of Uranium Resource Exploration and Evaluation Technology,Beijing 100029,China;China National Uranium Co.Ltd,Beijing 100013,China;;School of Earth Sciences and Mineral Resources,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中核集团核工业北京地质研究院,北京100029 [2]中核集团铀资源勘查与评价技术重点实验室,北京100029 [3]中国铀业有限公司,北京100013 [4]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《大地构造与成矿学》2018年第5期893-907,共15页Geotectonica et Metallogenia

基　　金：国家自然科学基金青年基金项目(41502097);中国核工业地质局地勘费科研项目"华北陆块北缘不整合面有关的铀矿成矿条件及远景评价";国防科技工业局核能开发项目"华北陆块北缘铀多金属矿综合评价技术研究";国土资源科技创新团队"铀矿成矿理论与深部找矿技术"培育计划联合资助

摘　　要：辽东半岛是胶-辽-吉古元古代造山带的一部分,经历了古元古代早期裂谷作用和古元古代末期碰撞造山过程。裂谷阶段形成了A型花岗岩(2.09~2.18 Ga)、辽河群沉积(2.05~1.93 Ga)。1.90~1.93 Ga期间裂谷闭合碰撞造山,辽河群遭受强烈变形、变质。1.83~1.90 Ga造山带构造折返,伴随垮塌、软流圈地幔上涌,发生区域退变质作用,形成造山后环斑花岗岩、斑状花岗岩、碱性正长岩和花岗伟晶岩。1.83 Ga辉绿岩的出现标志地壳进入伸展张裂阶段。尽管辽东地区古元古代铀矿化的类型多样,包括单铀型(3075铀矿床、410铀矿床)、铁-铀型(405铀矿床)、铁-硼-铀型(翁泉沟含铀铁硼矿床),但是铀的成矿时代一致,集中在1.83~1.90Ga。辽东地区古元古代末期的铀成矿作用形成于太古宙龙岗地块与狼林地块碰撞造山之后的伸展环境,可能与碰撞造山晚期俯冲陆块的构造折返和/或造山带垮塌及软流圈地幔上涌加热下地壳有关。As part of the Paleoproterozoic Jiao-Liao-Ji orogenic belt,the eastern Liaoning peninsula underwent rifting in the early Paleoproterozoic and collisional orogenesis in the late Paleoproterozoic.The A-type granitoids(2.09 to 2.18 Ga)and Liaohe Group(2.05 to 1.93 Ga)were formed in the rifting process.The rift was closed due to collisional oogenesis at 1.90 to 1.93 Ga which led to the extensive deformation and metamorphism of the Liaohe Group.During 1.83 to 1.90 Ga,exhumation took place as a consequence of orogenic collapse and subsequent upwelling of asthenospheric mantle which is marked by the regional retrograde metamorphism,intrusion of post-orogenic rapakivi granites,porphyritic granites,alkaline syenites and granitic pegmatites.The^1.83 Ga diabase dykes indicated a regional crustal extension.The types of uranium mineralization in the eastern Liaoning peninsula are diverse,including single U,Fe-U,Fe-B-U mineralization,however,they are coeval with ages of 1.83 to 1.90 Ga.Therefore,the regional uranium mineralization in the eastern Liaoning peninsula of the Paleoproterozoic Jiao-Liao-Ji orogenic belt was formed in post orogenic extensional setting following the collision between the Archean Longgang and Langlin blocks.

关 键 词：胶-辽-吉造山带 铀矿床 古元古代 碰撞造山 

分 类 号：P611[天文地球—矿床学]