西藏甲玛铜多金属矿有用元素空间分布特征及地质意义  

Research on the spatial distribution of useful elements in the Jiama copper-polymetallic deposit,Tibet,China

作　　者：郭衍游[1] 王焕[2] 畅哲生 唐晓倩[4] 丁帅[4] 

机构地区：[1]淮海工学院,江苏连云港222005 [2]中国地质科学院矿产资源研究所,北京100037 [3]西藏华泰龙矿业开发有限公司,拉萨850000 [4]成都理工大学地球科学学院,成都610059

出　　处：《成都理工大学学报（自然科学版）》2011年第6期684-688,共5页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家科技支撑项目(2006BAB01A01);中央公益性行业科研专题(200911007-02);国土资源部青藏专项(1212010818089);国土资源地质大调查项目(1212010733803);西藏华泰龙矿业开发有限公司委托项目(E0804)

摘　　要：为了查明西藏甲玛多金属矿主要矿体有用元素在不同海拔高度的三维空间分布规律,通过钻孔和探槽取样,利用原子吸收法和等离子体原子发射光谱法测试了21 911个化学样品,然后利用等值线图法,得到了6种有用元素在矿体内部的三维空间分布。结果表明:Au、Ag、Cu元素矿体底部有一个高值中心,随着高度增加,高值范围以此中心逐渐向外扩散,并以4.5km海拔高度为界,以下呈较明显的环形扩散,以上呈较明显的线形扩散。Mo元素在矿体底部有2个富集中心,随着高度增加,Mo的分布范围较Cu更大,但是大体上仍表现出环形向外扩散的特征。Pb和Zn的分布规律与其他4种元素完全不同,主要分布于海拔高度>4.5km区域,并且分布范围小。结合元素地球化学特征及岩浆热液成矿特点,可以判断甲玛主矿体的底部存在一个含矿中心,为岩浆热液上升中心,由底向上,呈环状向外扩散,在矿体上部受线性构造影响,呈近似带状分布。该矿床有用元素空间分布具有典型的岩浆热液型矿床分布特征。In order to investigate the spatial distribution characteristics along different altitude ranges of the useful elements in the main ore bodies,data of 21911 chemical samples are used to draw contours of 9 different altitude ranges from bottom to top of the ore bodies.The samples were collected from drill-holes and investigation pits and measured by atomic absorption method and plasma atomic emission spectroscopy.The results show that Au,Ag,Cu concentrate around a center on the bottom of the ore body and are diffused from bottom to top,showing an arc-like shape below 4.5 km altitude and a belt-like shape above 4.5 km altitude;Mo concentrates around two centers on the bottom of the ore body and is diffused farther compared with Cu,and also shows an arc-like shape;Pb,Zn show totally different characteristics and concentrate in a region above 4.5 km altitude with a small range.Considering the element geochemical features and magmatic hydrothermal mineralization,it is concluded that an ore-containing center lies on the bottom of the main ore body and this is also the center of the rising hydrothermal materials;the useful elements are diffuse arc-like from bottom to top and show a belt-like shape on the top of the ore bodies with the influence of linear structures.The distribution of useful elements of the Jiama deposit is identical to that of the typical magmatic hydrothermal deposits.

关 键 词：甲玛铜多金属矿 空间分布特征 有用元素 冈底斯成矿带 

分 类 号：P618.41[天文地球—矿床学]