山东新城金矿控矿因素分析与深部找矿预测

【作者】 王广强；

【导师】 高建国；

【作者基本信息】 昆明理工大学 ， 矿产普查与勘探， 2011， 硕士

【摘要】 新城金矿位于华北陆块胶辽隆起的胶北-胶莱断隆区西北部,沂沭断裂带东侧焦家金矿带上,区内太古宇-元古宇变质岩带发育,岩浆活动频繁而强烈,断裂构造极其发育,地质背景复杂,成矿条件优越。矿山于1980年建成投产,实际生产能力矿石93.41万吨/年,至2009年底累计生产黄金51.12t。经过31年的开采,至2008年底,新城金矿保有资源储量4549151t,金金属量15022Kg,仅可服务4.88年,属于资源中度危机矿山。论文选择这一颇具前景的地区开展综合研究,通过对新城金矿床的区域地质、矿区地及矿床地质的研究,重点分析控矿因素和找矿标志,总结成矿规律及矿床成因,在综合上述控矿和成矿信息的基础上,对矿床进行深部找矿预测。论文取得的主要认识如下：1、前寒武纪变质岩系是金矿原始矿源层,郭家岭超单元为金矿体的赋矿围岩,并与玲珑超单元为金成矿提供直接矿源。2、矿体严格受断裂构造控制,多赋存于主断裂面断层泥的下盘,说明成矿前的断层泥对含矿热液有阻挡作用,其下盘的破碎蚀变带有利于矿液运移、聚集、沉淀成矿；矿体赋存于主构造断裂面起伏较大产状变缓部位。由于控矿断裂叠加了多次继承性活动,造就了主构造断裂面的起伏,在断裂面起伏向外的突出部位是矿体赋存的主要有利部位。3、矿化富集受构造蚀变岩带控制,其构造活动强烈部位,岩石蚀变程度高、裂隙发育、孔隙度大,有利于矿液渗透、扩散和交代。该部位蚀变作用多次迭加易形成富矿体,矿体多产于黄铁绢英岩化碎裂岩带和黄铁绢英岩化花岗闪长质碎裂岩带。4、地球化学异常总体特征都具有Au、Ag、Cu、Pb、Zn的内中带异常,而且都有前缘晕特征指示元素Hg、As、Sb、Bi、W中外带异常,或与尾晕指示元素Mo、Co异常共存,指示矿体向深部延伸还很大。5、新城金矿矿床的形成主要受以胶东群、荆山群为主体的前寒武纪变质岩系基底；北东、北北东向断裂构造；元古代重熔型岩浆岩及中生代燕山期岩浆岩三大控矿因素复合控制。此外,韧性剪切带、热液蚀变和成矿流体也对金矿的富集成矿起到了重要的作用。因此,控矿因素对该区金成矿起着决定性作用。本文通过对矿区成矿地质条件、控矿因素、成矿规律的分析研究,得出新城金矿的六个预测靶区。更多还原

【Abstract】 Xincheng gold mine is located in the northwest of north China land mass uplifted Jiaobei Jiaoliao-Jiaolai fault uplift, Yishu fault zone east of jiaojia gold belt. In the Region Archean-Proterozoic metamorphic belts development, magmatic activity frequent and intense, fault structure developments, geological background is complex, and metallogenic conditions is superior.After 31 years of mining, to the end of 2008, Xincheng gold mine reserves resources retained 4549151t, metal quantity 15022Kg, can only service 4.88 years, belong to resources moderate the crisis mines.Xincheng gold deposit is one of the mines to be exhausted in China .In order to solve problems of prospecting predication and exploration, reserches have been carried out by analizing the regional ,local geology and characteristics of geochemistry comprehensively, especially the ore controling factors and prospecting signs. On the basis of the work, conclusions and achievements are obtained as following:1、Precambian metamorphic rocks are the source bed of the gold mines. Linglong and Guojialing super-unit offer ore-forming material sources for mineralization, and Guojialing super-unit is the wall rock of the gold ore deposits.2、Ore bodies controlled by the faults is hosted by the lower wall of the gouge,which is developed on the main fault surface,indicating that gouge obstruct the hydrothermal migration. Fractured and alteration zone located in the is favourable to migration, enrichment and deposits of the ore forming fluid. Orebodies occur in the Lord of the tectonic fractures ups and downs in the shape of large slow sites. Due to the ore-controlling fracture superposition many inheritance activities, so contributed to the main tectonic fracture surface of the ups and downs, and the outward in fractures ups and downs of prominent part is orebodies occur mainly favorable positions.3、Controlled by the tectonic altered rocks, in a strong position tectonic activity of mineralized zone of enrichment, rock altered degree is high, fracture, porosity, permeability, is conducive to mineral liquid penetration, diffusion, and accountability. This site altered function repeatedly superposition easily form rich ore body, Orebody from prolific in the pyrite ore phyllic cataclasite zone and pyrite phyllic granodioritic cataclasite zone.4、Geochemical anomaly shows that Au、Ag、Cu、Pb、Zn are anormal in inner-middle zone,and middle-outter anormalous zone is reflected by the Post-ore halo elements, including Hg、As、Sb、Bi and W, or with the end of halo indicator elements Mo, Co abnormalities coexist, indicating that the ore body extension to deep is still very great.5、Xincheng gold mine in the formation controlled compoundly by three ore-controlling factors such an the Precambrian metamorphic basement as the main body of jiaodong groups and JingShan group, NE, NNE faults, Yuan ancient remelting type of magmatic rocks and Mesozoic yanshan magmatite. In addition, ductile shear zone, hydrothermal altered and ore-forming fluid played an important role to the enrichment of gold. This article obtained six gold predicted targets through to analysis and research the ore-forming geological conditions of the mine, the geochemical characteristics, ore-controlling factors and metallogenic regularities.更多还原