中条-熊耳多期裂谷开合构造及其深部找矿  

Opening and closing structure of Zhongtiao-Xionger multi-stage rift valley and deep prospecting

作　　者：刁谦 真允庆 牛树银 孙爱群 宋涛[1] 孙璐 DIAO Qian;ZHEN Yun-qing;NIU Shu-yin;SUN Ai-qun;SONG Tao;SUN Lu(East China Geological Exploration Bureau of Nonferrous Metals of Jiangsu Province,Nanjing 210093,China;The Third Geoexploration Bureau,China Metallurgical Geology Bureau,Taiyuan 030002,China;Hebei GEO University,Shijiazhuang 050031,China)

机构地区：[1]江苏省有色金属华东地质勘查局,南京210093 [2]中囯冶金地质总局三局,太原030002 [3]河北地质大学,石家庄050031

出　　处：《桂林理工大学学报》2022年第1期29-45,共17页Journal of Guilin University of Technology

基　　金：江苏省省级地质勘查专项资金项目(苏财建[2017]160号)。

摘　　要：通过对华北“南部古陆块”(中条山-王屋山-熊耳山及东秦岭地区)的初步研究,认为该区地壳的拉张伸展与隆升挤压活动,就像“拉手风琴”一样,贯穿于地质构造演化的始终。这种开合构造旋回,既有“大开大合”,又有“小合小开”类型。开合构造旋回按“三步曲”迁移,具有向南性、旋回性及成矿变异性特征。自北至南有逐步变新的趋势,2.5~1.73 Ga期间,该区经历了近EW向以伸张为主的优地槽绛县群沉积建造,演化成NE向以沉降为主的冒地槽中条群沉积建造,实际为两次裂谷型建造的记录,即受控于绛县运动和中条运动;同时,可能由于碰撞造山作用,相继沉积了磨拉石建造的担山石群;紧接着,在其东南部的嵩山、熊耳山和崤山一带的广大区域,喷发(溢)了以中基性火山岩为主的双峰态熊耳群沉积建造,在局部地区见有A型花岗岩侵入,亦为被动大陆裂谷环境,无疑与元古代地幔柱活动密不可分,据此可称其为中条-熊耳多期裂谷的“前世”。更明显的是,在东秦岭地区(含熊耳群)以中生代燕山运动为主,从地震层析资料证实,本区深部低速高导层为柱状体,可视为中条-熊耳多期裂谷的“今生”,显然为典型的复合地幔柱构造范例。在中条山-王屋山地区,成矿作用是以元古宙铜矿(含金、钼、钴)为主;而熊耳山-东秦岭地区,虽然亦有少量中元古代和古生代的金矿床(含钼、铜)分布,但多以印支期和燕山期金、钼(含钨、铅锌、铍)矿床为主,成为我囯重要的金属矿集带。区内矿床成矿类型繁多,基本与透岩浆成矿热液侵位机制有关。据统计,中型、大型-特大型矿床均受地壳张裂(开)环境或受开合构造转换地段控制。针对当前中条-熊耳多期裂谷的具体勘查情况,提出了8项关键找矿建议。Based on preliminary study of the“southern ancient land block”in North China(Zhongtiaoshan-Wangwushan-Xiongershan and East Qinling Mountains),the stretching,extension and uplift and compression of the crust in this area occur throughout the tectonic evolution of the earth.This kind of open-close tectonic cycle shows the phenomenon of“big opening and big closing”and“small closing and small opening”.The migration of opening-closing tectonics cycle according to“three steps”is southward,and the geological age of multi-stage rifting and mineralization tends to change gradually from north to south.During the period of 2.5 Ga to 1.73 Ga,the area experienced the sedimentary formation of Jiangxian Group of eugeosyncline dominated by extension in the near EW direction,and evolved into the sedimentary formation of Zhongtiao Group of miogeosyncline dominated by subsidence in the NE direction.It is actually a record of two rift-type constructions,controlled by the Jiangxian Movement and the Zhongtiao Movement.In the meantime,the Danshan Group of molasse formation might have deposited successively due to collision orogeny.In the vast area of Songshan,Xiongershan and Xiaoshan in the southeast,the bimodal Xionger Group sedimentary formation dominated by intermediate-basic volcanic rocks erupted(overflowed).There are A-type granite intrusions in some areas,and it is also a passive continental rifting environment,undoubtedly inseparable from the Proterozoic mantle plume activity.Accordingly,it can be called the“previous life”of the Zhongtiao-Xionger multi-stage rift.In the eastern Qinling area(including the Xionger Group),the Mesozoic Yanshan Movement is dominant.Confirmed from seismic tomographic data,the deep low-velocity and high-conductivity layers are columnar bodies,as the“present life”of the Zhongtiao-Xionger multi-stage rift,obviously a typical example of composite mantle plume structure.In the Zhongtiaoshan-Wangwushan area,the mineralization is dominated by Proterozoic copper deposits(containing Au

关 键 词：大陆裂谷 开合构造 复合地幔柱构造 深部找矿 中条山 王屋山 熊耳山 

分 类 号：P612[天文地球—矿床学]