内蒙古东升庙、甲生盘中元古代SEDEX矿床同生断裂活动及其控矿特征  

ORE-CONTROLLING SYNCHRONOUS FAULTS OF MESOPROTEROZOIC DONGSHENGMIAO AND JIASHENGPAN SEDEX-TYPE ORE DEPOSITS, INNER MONGOLIA

作　　者：彭润民[1] 翟裕生[1] 王志刚[2] 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]化工部内蒙古地质勘查院,呼和浩特010074

出　　处：《地球科学（中国地质大学学报）》2000年第4期404-409,共6页Earth Science-Journal of China University of Geosciences

基　　金：原地质矿产部重点基础研究项目!(No .95 0 110 7);国家"973"项目!(No .G19990 43 2 15 )

摘　　要：东升庙Zn -Pb -Cu矿床和甲生盘Zn -Pb矿床具有鲜明的层控特征 ,前者产在中元古界狼山群二组中 ,后者则局限在中元古界渣尔泰山群阿古鲁沟组第二岩段内 .二者产出层位相当 ,根据 (1)含矿地层有岩相 (性 )的突变 ;(2 )含矿岩段地层厚度顺走向和倾向变化性大、厚度突变现象明显 ,并存在层间砾岩和滑塌角砾岩 ,角砾成分为大小不一的白云石大理岩块、碳质千枚岩、石英团块、凝灰岩块、变粒岩块、变质火山岩碎块、黑云母片岩碎块 ;(3)矿体总体呈层产出 ,但有一些Zn -Pb -Cu矿体突然变薄 ,甚至消失 ,形成鱼头状矿体 ,且发育角砾状矿石 ,角砾成分与层间砾岩的相同 ,且还含Pb -Zn矿石或Py矿石角砾 ;(4)火山岩或凝灰岩夹层顺同生断裂带分布 ,确认其唯一容矿岩组形成过程中有明显的同生断裂活动 .同生断裂系统是含矿热水和火山熔浆进入沉积盆地的通道 ,是两大矿床形成的有利因素 ,但其活动频率、规模与持续时间的差异 ,也造成不同的矿床规模和矿体分布 .东升庙矿床同生断裂活动时限相对长、矿床规模大、矿种多 .甲生盘矿床同生断裂活动时间短 ,矿床规模为大型 .s: The Dongshengmiao Zn Pb Cu sulfide ore deposit hosted by the only ore bearing 2nd formation of the Mesoproterozoic Langshan Group and the Jiashengpan Zn Pb sulfide ore deposit hosted by the 2nd member of the Agulugou Formation of the Mesoproterozoic Zhaertai Group are both obviously strata bound and equivalent in their occurrence horizons. It is believed that the synchronous faulting occurred in the only ore bearing 2nd formation of Langshan Group and in the 2nd member of the Agulugou Formation, supported by the following evidences: (1) The sudden changes in lithofacies occurred in the ore bearing strata; (2) The thickness of the ore bearing strata suddenly varied along the strike and dipped with intraformational conglomerates, and olistolithes; (3) The Zn Pb Cu orebodies suddenly thickened and thinned or even wedged out; (4) In some Zn Pb, Zn Pb Cu and Zn Cu orebodies occurred the brecciated structure ores containing some blocks and fragments of dolomite marble, carbonaceous phyllite, quartzite, tuffs, granulites, metavolcanite, biotite schist and even Zn Pb or Py ores; (5) Some basic volcanic rocks and ruffs occurred in the linear distribution. The synchronous fault, favorable for the formation of the Dongshengmiao and Jiashengpan ore deposits, served as the path for both the volcanic eruption and the mineralized fluid exhaling into the ore bearing basins during the Mesoproterozoic. The variations in scale and history of the synchronous fault with different secondary depositional basins suggested the unevenness of the extensional processes resulting in the difference in the mineralization intensity and orebody distribution. The Dongshengmiao ore deposit had a longer history of synchronous fault than the Jiashengpan ore deposit. In this sense, the Dongshengmiao ore deposit is defined as the super large deposit, but the Jiashengpan ore deposit as the large one.

关 键 词：同生断裂 SEDEX矿床 控矿构造 多金属矿床 

分 类 号：P618.202[天文地球—矿床学]