塔里木盆地库车坳陷砂岩型铀矿成矿潜力分析

1.中陕核工业集团二一四大队有限公司,陕西 西安 710064; 2.成都理工大学沉积地质研究院,四川 成都 610059; 3.长庆油田分公司 勘探部,陕西 西安 710000; 4.中陕核工业集团二一一大队有限公司,陕西 西安 710024

库车坳陷; 上新统库车组; 砂岩型铀矿; 成矿地质条件

Analysis on mineralization potentiation of sandstone type uranium in Kuche depression of Tarim Basin
ZHUANG Hong-hong1,2,MAO Zi-qiang1,ZHANG Tao3,

(1.214 Battalion,Co.,Ltd.,In China Shanxi Nuclear Industry Group Company,Xi'an 710024,China; 2.Research Institute of Sedimentary Geology,Chengdu University of Technology,Chengdou,610059,China; 3. Exploration Department,Petrochina Changqing Oil Field Company,Xi'an 710000,China; 4.211 Battalion,Co.,Ltd.,In China Shanxi Nuclear Industry Group Company,Xi'an 710024,China)

Kuche depression; Pliocene Kuche group; sandstone-type uranium deposits; ore-forming geological conditions

DOI: 10.13800/j.cnki.xakjdxxb.2015.0314

备注

库车坳陷位于塔里木盆地北缘,新近系库车组出露面积广,沉积厚度大,为客观认识塔里木盆地库车坳陷新近系库车组的成矿潜力,通过对成矿地质条件分析认为,上新统库车组发育以河流相为主的一套杂(红)色陆相碎屑岩系,具有有利的泥-砂-泥结构; 构造抬升控制着砂岩型铀成矿作用的发生,成为地层中铀活化、淋滤的有利通道; 盆地北缘蚀源区的下元古界绿片岩,下二叠统火山岩及凝灰岩和华力西中、晚期花岗岩体提供丰富的铀源; 具有完善的地下水动力系统,补-径-排体系完善; 铀成矿与含油气构造具有空间上的一致性,油气参与了铀成矿,发育的深大断裂沟通了深部烃源岩与上部圈闭,盆地深部油气逸散的有利地带,为砂岩型铀矿成矿提供了还原障; 同时盆地具有有利的地形地貌条件。由此推断,塔里木盆地库车坳陷砂岩型铀矿成矿条件较好,可作为有利的勘查目标区。

Kuche depression is located in the north rim of Tarim Basin, the outcropped of Kuche Formation(Neogene System )in Kuche depression is wide, and the sedimentary thickness is large, in order to understand the metallogenic potential of Kuche Formation(Neogene System )in Kuche Depression of Tarim Basin, through the analysis of metallogenic geological conditions, the lithology of Pliocene Kuche Formation is mainly variegated continental clastic rock series(red)of fluvial facies, with favorable mud-sand-mud structure.Tectonic uplift controlled the occurrence of the sandstone type uranium mineralization, which became the favorable channel for activating and leaching of uranium in the formation.The north rim of the basin is the region of exterior, which can provide abundant uranium source, including the green schist of Early Proterozoic group, the volcanic rock of Early Permian and the granite rock of middle-late Variscan.The groundwater dynamic system is perfect with recharge-runoff-discharge area.he space Uranium mineralization with oil and gas construction are consistent, the oil and gas participated in the uranium mineralization, the deep fault became the communication of deep hydrocarbon source rock and the Upper trap, the zone of basin of deep oil and gas from escaping is favorable reducing barrier for sandstone type uranium mineralization.At the same time, Depression has favorable terrain conditions. From what has been discussed above, safely draw the conclusion that sandstone type uranium mineralization condition is good in Kuche depression of Tarim Basin, which can be used as a favorable exploration target area.