山西省夏县洞沟金矿土壤地球化学特征及成矿预测

发布时间：2018-03-21 21:06

  本文选题：土壤地球化学　切入点：异常下限　出处：《成都理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：山西省夏县洞沟金矿研究区大地构造位于华北大陆亚板块南部鄂尔多斯地块与河淮地块接触带南部,太行山地区中条山隆起中段。地层出露较全,构造发育,岩浆活动强烈,成矿地质条件优越。本次1:1万土壤地球化学测量,拟结合前人的地质研究及其地质特征圈出并确定最有利的勘查地段,找出最有力的成矿远景区,并总结其地球化学特征。为下一步的勘查工作提供最有力的证据及找矿方向。本文首先总结了本区的地质背景并对土壤元素的浓度克拉克值、元素变异系数、偏度等地球化学特征进行了统计和分析。通过对土壤化探数据统计分析得出土浓集克拉克值大于1的元素依次是Zn、Au、W、Ba、Bi、Pb、As、Sb、Hg,说明该类元素具有一定次生富集倾向,其中Hg、Sb、As、Pb等富集程度较高;元素变异系数大于1的元素有Au、Ag、Pb、Sb,表明研究区土壤中这些元素分布不均匀,离散程度大,分异性强,有富集的趋势,是成矿较有利的地球化学条件;Ag、Cu、Pb、Au、Mn、Sn等六个元素其偏度值较大,说明它们可能受到后期的地球化学作用的影响,使其在地质体中的含量不服从正态分布。并且通过对研究区各个地质单元分别统计,可以得出构造破碎带成矿元素含量明显高于其它地质单元。通过对比分析迭代法、累积频率法、盒须图法进行化探数据处理,并得出异常下限。从中选取最切合实际的异常下限值。利用地质软件完成16幅地球化学图及16幅地球化学异常图。其中:异常点个数较多的元素为Zn、Hg、Cu、Mo、Ag、As、Pb、Au、Sn等,大部分元素达到3级浓度带,其中强度较高的元素有Cu、Au、Pb等元素;大多数元素的异常较分散,异常规模差异较大,异常浓集中心较为明显;各元素异常分布具有一定的规律性。对测区土壤地球化学数据进行多元统计分析,从元素相关性分析可以得出Au与As、Bi、Hg、Ba、Cu、W相关性较强,因此这些元素可作为直接找矿的指示元素;从聚类分析可以划分出①Ag、Pb、Zn、Mo;②Co、Ni、Cu、As、Sb、Bi;③Mn;④Ba、W、Hg、Au;⑤Sn等5种元素组合;通过因子分析从研究金的角度出发可以看出Au与F3、F4因子成正相关,因此Au与Hg、Ba、W、As、Sb、Bi关系密切。与F1、F2、F5成负相关,因此Au与Co、Cu、Mn、Ni、Ag、Pb、Zn、Mo、Mn、Sn关系不甚密切。总之各元素组合及其相关程度,可以反映主要成矿元素的次生富集特征。根据对土壤地球化学元素的综合异常特征分析,综合异常AP7元素组合Ag、Pb、Au、Hg、Zn、Mo、Cu、Sb、As、W、Sn、Bi,∑NAP值16.74,排序1。异常位于测区东部洞沟一带,对应大理岩地层,异常元素组合复杂,表现中高温和中低温元素组合特征,以中低温元素为特征,也可以认为矿床剥蚀浅,由46个单元素异常组成,异常处于构造转折部位内侧,成矿条件有利,潜力大。在综合异常的基础上结合相关地质背景圈出的成矿远景区,位于矿区中部,面积约8.9km2。预测靶区岩性主要为绢片岩、白云石大理岩、石英岩;靶区中间发育有两处构造破碎带,根据对其地球化学特征统计,发现金矿化主要是发生在此区域,因此金矿化与此破碎带有着密切的关系。
[Abstract]:Shanxi Xiaxian Donggou study area tectonic gold deposit is located in the North China sub plate, South Block and Ordos Hehuai block contact zone of southern Taihang Mountain area. The middle strata in uplift over the whole tectonic development, strong magmatic activity, metallogenic geological condition is superior. The 1:1 000 soil geochemical survey, to determine the most favorable the exploration area combined with the geological and geological characteristics of the previous research circle and find out the most powerful prospecs, and summarizes its geochemical characteristics. To provide the most powerful evidence for the exploration work in the next step and prospecting direction. This paper summarizes the geological background of the region and the soil elements concentration Clark value. The element variation coefficient, skewness and other geochemical characteristics are collected and analyzed. Based on the soil geochemical data statistical analysis was unearthed from the concentration Clark values greater than 1 elements are Zn, Au W, Ba, Bi, Pb, As, Sb, Hg, indicating that this kind of element has a secondary enrichment tendency, including Hg, Sb, As, Pb and other high concentration elements; variation coefficient is greater than 1 of the elements are Au, Ag, Pb, Sb, indicating that the uneven distribution of these elements in soil discrete degree, big difference, there is a trend of enrichment, is a favorable metallogenic geochemical conditions; Ag, Cu, Pb, Au, Mn, Sn and other six elements of the skewness value is large, indicating that they may be affected by the geochemistry of late, the content in the geological body obey the normal distribution. And through the statistics of various geological units in the study area, can draw the structural fracture zone of ore-forming elements was significantly higher than that of other geological units. Through the comparative analysis of the iterative method, cumulative frequency method, box chart method for geochemical data processing, and the anomaly threshold. Select the most practical the use of value. 鍦拌川杞�浠跺畬鎴�16骞呭湴鐞冨寲瀛﹀浘鍙，

本文编号：1645543