松辽盆地新生代构造演化对砂岩型铀矿成矿的控制作用——来自磷灰石裂变径迹的证据  

The controlling effect of Cenozoic tectonic evolution on the mineralization of sandstone-type uranium deposits in the Songliao Basin:evidence from apatite fission tracks

作　　者：吏成辉 程银行 王铁军[3] 王少轶 张天福 程先钰 张夏炜 李艳锋 LI Chenghui;CHENG Yinhang;WANG Tiejun;WANG Shaoyi;ZHANG Tianfu;CHENG Xianyu;ZHANG Xiawei;LI Yanfeng(Tianjin Center,China Geological Survey,Tianjin,300170;Key laboratory of uranium geology,China Geological Survey,Tianjin,300170;Sinosteel Tianjin Geological Research Institute,Tianjin,300181;Hebei GEO University,Shijiazhuang,050031)

机构地区：[1]中国地质调查局天津地质调查中心,天津300170 [2]中国地质调查局铀矿地质重点实验室,天津300170 [3]中钢集团天津地质研究院有限公司,天津300181 [4]河北地质大学,石家庄050031

出　　处：《地质学报》2020年第10期2856-2873,共18页Acta Geologica Sinica

基　　金：中国地质调查项目(DD20190813);国家重点研发计划(2018YFC0604200);国际地球科学计划(IGCP675);国家重点基础研究发展计划(973计划,项目编号:2015CB453000)资助的成果。

摘　　要：本文针对松辽盆地北部隆起区的4个钻孔13件样品系统展开了磷灰石裂变径迹测试,揭示了松辽盆地新生代构造演化对砂岩型铀矿床的限制作用。13件磷灰石裂变径迹测试结果表明,松辽盆地北部晚白垩世以来的构造演化过程主要经历了3期快速隆升事件:(1)晚白垩世—始新世(71~48 Ma),期间以8~56 m/Ma的平均速率隆升,盆地北部整体呈抬升状态;(2)早渐新世—中新世(36~18 Ma),期间以24~49 m/Ma的平均速率隆升,盆地北部呈差异性抬升过程,第二期抬升事件隆升强度和持续时间较第一期抬升事件略低;(3)中新世-至今(18~0 Ma),期间以2~19 m/Ma的平均速率隆升,盆地北部缓慢抬升,构造活动较弱,三期构造抬升事件与太平洋板块俯冲速率和方向转向密切相关。结合前人低温热年代学数据,针对南部地区钱家店铀矿床成矿年代学成果研究发现,新生代以来的构造抬升事件伴生其后均成藏有砂岩型铀矿,砂岩型铀成矿与新生代构造密切相关,尤其与中新世末次隆升事件紧密相关,成矿过程延续至今。This paper undertakes a systematic study of 13 samples from 4 boreholes in the northern Songliao Basin by conducting apatite fission track tests.The study shows that the Cenozoic tectonic evolution of the Songliao Basin has a controlling effect on the sandstone-type uranium deposits.According to the thirteen AFT tests,the northern area of the Songliao Basin experienced three major rapid tectonic uplifts since late Cretaceous:1)from the Late Cretaceous to Eocene(71~48 Ma),the whole northern basin experienced a major uplift at an average rate of 8~56 m/Ma;2)From the Early Oligocene to Miocene(36~18 Ma),the northern basin underwent a differential uplift at an average rate of 24~49 m/Ma,the second uplift showed slightly lower intensity and was of shorter duration than the first one;3)since Miocene(18~0 Ma),there was a weak tectonic and a slow uplift at an average of 2~19 m/Ma.The three tectonic uplifts were closely related to the subduction rate and moving direction of the Pacific plate.Based on the data from previous low temperature thermal chronology study as well as the research on the metallochronology of the Qianjiadian sandstone-type uranium deposit in the southern Songliao Basin,the tectonic uplifts since Cenozoic were accompanied by subsequent formation of sandstone-type uranium deposits.This indicates that the sandstone-type uranium mineralization is closely related to Cenozoic tectonic evolution,particularly to the tectonic uplift in the late Miocene,and the mineralization process continues to the present.

关 键 词：松辽盆地 磷灰石裂变径迹 砂岩型铀矿 新生代构造演化 太平洋板块 

分 类 号：P619.14[天文地球—矿床学]