内蒙古柴河源林场铅锌多金属矿产成矿预测研究

发布时间：2018-05-08 08:46

本文选题：地球化学 + 地球物理　；参考：《吉林大学》2015年硕士论文

【摘要】：研究区地处大兴安岭南麓,兴蒙造山带东段,位于兴安地块,东与松嫩地块接壤,西与额尔古纳地块接壤,经历了古亚洲洋构造域和古太平洋构造域两大演化阶段,以及西伯利亚板块和中朝板块间若干块体之间复杂的拼贴、演化历史。东乌珠穆沁旗复背斜的柴河源林场位于中生代断陷边缘,即东乌珠穆沁旗早华力西造山带上。区内地质构造复杂、火山作用和岩浆活动均较频繁。通过对研究区内地质、物化探信息及区域所处成矿带、典型矿床等成矿信息的综合研究,系统总结找矿信息的基础上,对研究区可能存在隐伏热液脉型铅锌多金属矿化体开展了成矿靶区预测。取得的认识如下:1、研究区处在东乌珠穆沁旗复背斜两个三级构造单元及其交接部位西部,该交接部位即为一深大断裂,成矿带内多金属成矿远景区即分布于此。通过对研究区高精度磁法测量,推测A区范围内存在北东向断裂构造及多条北西向次及断裂构造。结合成矿带内典型矿床资料,认为矿床类型为火山热液脉型,并受断裂构造的影响。2、研究区地质、化探工作揭示,在侵入岩(三叠世碱性花岗岩、侏罗世钠长斑岩)与多宝山组地层接触部位,元素异常显著,组合异常好,岩石矿化蚀变强烈,是找矿工作的重点地段,且角岩化多宝山组岩石可以作为岩浆热液活动的标志之一。3、研究区Pb、Zn、Mo、Ag、C u元素变异数均较大,元素在不同地质体中分配相对不均匀,容易局部富集,为多金属矿的形成奠定了物质基础,Bi、Sn、As、W、Au元素变异数较小,不易富集成矿。4、通过土壤测量数据R型因子分析可知,区内主成矿元素为Pb、Zn、Mo、Ag、Cu,土壤地球化学测量与激电异常结果显示,优秀土壤组合异常与中-高极化率异常、低电阻率叠加部位对找矿有很好的指导意义。5、在总结研究区的成矿模式与控矿条件基础上,认为研究区深部存在一定规模的铅锌多金属矿体。根据区内成矿预测标志,在研究区内圈定出3处成矿靶区(I级成矿靶区1处,II级成矿靶区2处)。其中,I甲级成矿靶区(A区)是区内最重要,最有成矿潜力的靶区。6、A区的工程验证,取得了不错的成果:地表槽探圈定出长约200m、宽约50m的铅锌多金属矿化带;深部钻探工程圈出铅锌多金属矿化体共计21条(铅、锌、钼、铜矿化体19条,金矿化体2条)。矿化集中发育在岩体与多宝山组地层接触带,岩石发育有碎裂岩化、隐爆角砾岩化,证明了研究区成矿靶区预测的正确性与可行性。整体上来看,研究区内成矿条件非常好,继续投入工作有望找到一定规模的铅锌多金属矿床。区内构造较为发育的区段,铅锌等多金属元素含量较为突出;元素异常高值受构造影响明显,与侏罗世钠长斑岩关系最为紧密。已发现矿(化)体多在钠长斑岩体及接触带附近,钠长斑岩受到震碎(隐爆)及热液叠加形成矿物质沉淀,形成矿(化)体。钠长斑岩为研究区内最主要的成矿母岩,也是研究区最为主要的找矿标志。
[Abstract]:The study area is located at the southern foot of the Daxing'an Mountains, the eastern section of the Xingmeng orogenic belt, the Xingan block, the Songnen block in the east and the Erguna block in the west. The study area has undergone two major stages of evolution: the Paleo-Asian Ocean tectonic domain and the Paleo-Pacific tectonic domain. And the complex collage and evolution history of several blocks between Siberia plate and Sino-Korean plate. The Chaiheyuan Forest Farm of East Wuzhumuqin Banner complex anticline is located on the edge of Mesozoic fault depression, that is, on the early Huaxi orogenic belt of East Wudhumuqin Banner. The geological structure in the area is complex, with frequent volcanism and magmatic activity. Based on the comprehensive study of geological, geophysical and geochemical exploration information and metallogenic information of the region, such as metallogenic belts and typical deposits, the paper systematically summarizes the ore-prospecting information. The metallogenic targets of the latent hydrothermal vein type lead-zinc polymetallic mineralization bodies in the study area were predicted. The understanding obtained is as follows: the study area is located in the west of the two tertiary structural units and their joint sites in the East Wudhumuqin Banner complex anticline, which is a deep fault, in which the polymetallic metallogenic distant spot is located in the metallogenic belt. Based on the high-precision magnetic survey in the study area, it is inferred that there are NE-trending fault structures, several NW-substructures and fault structures in the A area. Combined with the data of typical ore deposits in the metallogenic belt, it is considered that the deposit type is volcanic hydrothermal vein type and affected by fault structure. The geological and geochemical work in the study area reveals that the ore deposit type in the intrusive rocks (Triassic alkaline granites), Jurassic sodium porphyry) and Dobaoshan formation strata contact site, the element anomaly is remarkable, the association is abnormal, the rock mineralization alteration is strong, is the prospecting work key area, Moreover, the rocks of the hornstone Dobaoshan formation can be used as one of the indicators of magmatic hydrothermal activity. In the study area, the variances of element PBZZZMoAg-AgCu are large, and the distribution of elements in different geological bodies is relatively uneven, and it is easy to enrich locally. It lays a material foundation for the formation of polymetallic ore. The variation number of the elements is small and it is not easy to enrich the ore-forming elements. Through the analysis of R-type factors of soil survey data, it can be seen that the main metallogenic element in the area is PbZnZn-MoMo-AgAg-Cu.The results of soil geochemistry survey and induced electric anomaly show that the main ore-forming element in the area is PbZnZn-Mo-Ag-Cu. The excellent soil assemblage anomaly and medium-high polarizability anomaly, and the superposition of low resistivity have good guiding significance for ore prospecting. On the basis of summarizing the metallogenic model and ore-controlling conditions in the study area, It is considered that there is a certain scale of lead-zinc polymetallic ore bodies in the deep part of the study area. According to the metallogenic prediction criteria in the study area, three metallogenic target areas of grade I and I have been delineated in the study area, and one and two areas of grade II metallogenic target have been identified in the study area. It is the most important and the most potential target area in this area. The engineering verification of the target area. 6A area has obtained good results: the plumb-zinc polymetallic mineralization belt about 200m long and 50m wide has been delineated by the surface trough exploration, and the results are as follows: (1) the plumb-zinc polymetallic mineralization zone with the length of 200m and the width of 50m is determined by the surface trough exploration. A total of 21 Pb-Zn polymetallic mineralization bodies (19 lead, zinc, molybdenum, copper mineralization bodies and 2 gold mineralization bodies) have been formed in deep drilling engineering. The mineralization is concentrated in the contact zone between the rock body and the Dobaoshan formation, and there are cataclastic rocks and crypto-explosive breccia, which proves the correctness and feasibility of the prediction of ore-forming target in the study area. On the whole, the metallogenic conditions in the study area are very good, and it is expected to find a certain scale of lead and zinc polymetallic deposits. The contents of polymetallic elements such as lead and zinc are more prominent in the areas where the structure is relatively developed, and the high value of element anomalies is obviously influenced by the structure, which is most closely related to the Jurassic sodium porphyry. It has been found that the ore-forming bodies are mostly located near the sodium-porphyry and its contact zone. The Na _ (2 +) porphyry is crushed (imploded) and superimposed by hydrothermal to form mineral deposits and form ore-forming (metamorphic) bodies. Sodium porphyry is the most important ore-forming parent rock and the most important prospecting marker in the study area.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.2

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