青海加吾金矿地质地球化学特征研究

发布时间：2018-04-20 19:35

本文选题：青海省 + 地质特征　；参考：《长安大学》2015年硕士论文

【摘要】：位于青藏高原东北部同德—泽库印支期铜、铅、金成矿带中的加吾金矿,是武警黄金部队在前人工作基础上,经战略地质调查及预查工作中所发现,并认为经进一步勘探工作可取得重大找矿突破。但2008-2011年武警黄金部队在矿区进行金矿勘探工作中,施工的探槽、探坑及钻孔见矿效果均不理想,致使对该区找矿前景产生质疑。对前人成果资料进行综合分析的基础上,结合野外实际调查成果,开展了加吾金矿及所在区域的地质地球化学特征分析,以期揭示其进一步找矿潜力。论文主要取得以下认识:1、1:20万区域地球化学特征研究结果表明:该区中下三叠统隆务河组(T1-2l)地层中,Au、W、As、Sb、Hg、Bi等元素呈相对富集状态,且离散程度较大,是具有寻找金、钨、锑矿潜力的赋矿地层单元;区域内元素主要分为六个组合,其中,Au-Sb-Ag-AsW-Bi-Cd-Sn组合主要反映Au的矿化富集特征,可作为研究区寻找金矿的指示元素组合;区域元素异常分布特征显示出,中下三叠统隆务河组(T1-2l)与断裂构造对异常分布和其形态具有明显的控制作用;区域内共圈出综合异常7个,其中Ht1、Ht2综合异常反映为已知金矿体异常,尤其是加吾金矿所在Ht1综合异常,异常规模大、强度高、浓集中心明显、元素组合好,表明该矿区进一步找矿潜力较大。此外,Ht5综合异常具有较好的找矿潜力,Ht3、Ht6、Ht7综合异常有一定的找矿希望。2、矿区地质特征显示:矿区地层以中下三叠统隆务河组的一套硬砂质长石-泥质细碎屑岩(T1-2l1-3)为主。其中,碳质板岩夹变质砂岩段(T1-2l3)矿化蚀变较强,是矿区的主要赋矿层位;矿区内构造变形强烈,断裂发育,NW向和EW向断裂既是矿区主要断裂,也是主要的控矿、容矿断裂,并控制着矿体的产出;矿区岩浆岩以印支期中酸性侵入体为主,主要为花岗闪长岩体和花岗斑岩脉,均与成矿关系密切;金矿体主要产于碳质板岩层间破碎带、碳质板岩夹砂质板岩或碳质板岩与花岗岩体的接触带上;矿石类型以碎裂蚀变岩型和石英脉型为主;矿化类型有褐铁矿化、黄铁矿化、毒砂矿化、辉锑矿化等;围岩蚀变有硅化、碳酸盐化、绢云母化等。3、矿区元素富集变化特征显示,矿区内元素Au、Ag、As、Sb、Pb、W、Bi、Cd的富集系数及变化系数分别达到1.27~37.86、1.81~11.19,表明这些元素呈明显的富集状态且分布极不均匀,表明他们在局部地段富集成矿的可能性很大;花岗斑岩、石英脉、构造破碎带中,Au的相对富集系数和变化系数分别达到1.41~1.30、1.68~3.32,表明这些地质单元对金的迁移富集影响作用很大。4、矿区元素主要分为三个组合。其中,Au-Ag-As-W-Cd-Pb组合与区域上Au-Sb-AgAs-W-Bi-Cd-Sn组合相似,主要反映Au的矿化富集特征,可作为该矿区寻找金矿的指示元素组合。5、矿区稀土元素地球化学特征显示,矿区沉积岩为正常壳源成因,与卡林型金矿围岩稀土元素地球化学特征相似;矿区岩浆岩为陆壳俯冲作用下的产物,同时深部物质(下地壳、地幔)也参与了岩浆活动;碎裂蚀变岩型矿石是地层沉积岩经过成矿流体改造作用的产物,石英脉型矿石与矿区花岗闪长岩可能具有相同的物质来源。6、矿床元素的水平分带显示,矿体的前晕元素为As、Sb、Hg、Ba,矿上晕元素为Au、Ag、Cu、Pb、Zn、W,尾晕元素为Cd、Bi、Mo、Ni、Co。该分带特征同时显示出,小曲如沟的断裂蚀变带下部具有良好的找矿潜力,应该是寻找金矿的主要地段。
[Abstract]:Located in the northeastern part of the Qingzang Plateau, the gold deposits in the copper, lead and gold metallogenic belts in the Indo Zeku period of the eastern Qinghai Tibet Plateau are found on the basis of previous work on the previous work of the gold troops of the armed police force, and have been found in the work of strategic geological investigation and pre investigation. But the gold troops of the armed police force in the mining area have made gold in the mining area for 2008-2011 years. On the basis of comprehensive analysis of the data of previous achievements, the geological and geochemical characteristics of the geo gold deposit and its region are analyzed on the basis of the comprehensive analysis of the data of the previous achievements and the analysis of the geological and geochemical characteristics of the geo gold deposits and their regions in order to reveal their further prospecting. The main achievements of this paper are as follows: the results of the 1,1:20 ten thousand regional geochemical characteristics show that the elements of Au, W, As, Sb, Hg, Bi and other elements in the middle and lower three series of the middle lower strata of the area are relatively enriched and have a relatively large degree of dispersion, which are the ore bearing formation units that have the potential for gold, tungsten and antimony. The elements in the region are mainly divided into six. In combination, the Au-Sb-Ag-AsW-Bi-Cd-Sn assemblage mainly reflects the mineralization and enrichment characteristics of Au, which can be used as the indicator element combination for finding gold deposits in the study area. The anomalous distribution characteristics of regional elements show that the middle and lower three superposition of the Long Wu River group (T1-2l) and the fault structure have obvious control effect on the abnormal distribution and its morphology. There are 7 anomalies, among which Ht1 and Ht2 synthesis anomalies reflect the known gold ore body anomalies, especially the Ht1 comprehensive anomalies in the gold mine where the gold deposits are located. The anomalies are large, the intensity is high, the concentration center is obvious, and the combination of the elements is good, which indicates that the mining area has a great potential for further prospecting. In addition, the Ht5 synthesis anomaly has a good prospecting potential, Ht3, Ht6, and Ht7 have a certain comprehensive anomaly. The geological features of the ore prospecting are.2, and the geological features of the mining area show that the mining area is dominated by a set of hard sandy feldspar clay fine clastic rock (T1-2l1-3) in the middle and lower upper three series of the Long Wu River group. Among them, the carbonaceous slate metamorphic sandstone section (T1-2l3) has strong mineralization and alteration, which is the main ore bearing stratum in the mining area; the tectonic deformation is strong, the fault development, the NW direction and the EW direction fracture in the mining area. It is not only the main fault of the mining area, but also the main ore control, ore bearing fracture and controlling the output of the ore body. The magmatic rocks in the mining area are mainly the acid intrusive bodies of the Indo Chinese period, mainly the granitic diorite and granite porphyry veins, which are closely related to the mineralization, and the gold deposits are mainly produced in the fractured zone between the carbonaceous plate rocks, the carbonaceous slate sandwiched with sand and carbonaceous plates. On the contact zone of rock and granite, the ore type is mainly composed of fractured and altered rock type and quartz vein type, and the mineralization type is browning, pyrite mineralization, arsenopyrite mineralization and so on. The alteration of surrounding rock has silicification, carbonation, sericite and so on.3, and the enrichment and variation characteristics of the mineral elements show that the enrichment system of elements Au, Ag, As, Sb, Pb, W, Bi and Cd in the mining area The number and variation coefficient are 1.27~37.86,1.81~11.19 respectively, indicating that these elements are obviously enriched and are extremely uneven distribution, indicating that they are very likely to enrich the mineralization in the local area. In the granite porphyry, quartz vein and structural fracture zone, the relative enrichment coefficient and change coefficient of Au are respectively 1.41~1.30,1.68~3.32. The geological unit has a great effect on the migration and enrichment of gold, and the elements of the mining area are mainly divided into three combinations. Among them, the Au-Ag-As-W-Cd-Pb assemblage is similar to the Au-Sb-AgAs-W-Bi-Cd-Sn assemblage in the region, which mainly reflects the mineralization and enrichment characteristics of the Au, which can be used as the indicator element combination of the gold deposits in this mining area,.5, and the geochemical characteristics of the rare earth elements in the mining area display, The sedimentary rocks of the mining area are the origin of the normal crust source, which are similar to the geochemical characteristics of the rare earth elements in the Carlin type gold deposits. The magmatite in the mining area is a product of the subduction of the continental crust, while the deep substance (the lower crust, the mantle) also participates in the magmatic activity, and the fractured and altered rock type ore is the product of the formation of the sedimentary rocks through the transformation of the fluid of the ore-forming fluid. Type ore and granodiorite of mining area may have the same material source.6, and the horizontal zoning of the deposit elements shows that the halo elements of the ore body are As, Sb, Hg, Ba, and the ore halo elements are Au, Ag, Cu, Pb, Zn, and W, and the tail halo elements are shown in the same time that the lower part of the fracture alteration zone of the small curved gully has a good prospecting potential. It should be the main location for the search for gold.

【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.51

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