西藏马拉松多铜矿床地质特征及找矿潜力分析

马拉松多铜矿床位于藏东地区,产于著名的西南三江成矿带上。矿区出露地层为三叠系下统马拉松多组(T_1m)酸性火山岩和三叠系上统甲丕拉组(T_3j)碎屑沉积岩。矿区位于背斜核部一侧,断裂构造不发育。矿区总共出现3个黑云母二长花岗斑岩体,为高钾钙碱性系列—钾玄岩系列,同位素年龄(K-Ar法)为34. 6～40. 8 Ma,属喜山早期产物。矿区具面型蚀变特征,由中心至边缘的分带为钾硅化带—绢云母化—角岩化带—青磐岩化带。昂克弄岩体已全岩矿化形成矿体,矿体平面呈椭圆形,长约950 m,宽约800 m;剖面上呈不规则柱状,矿体平均垂直厚度315 m;矿体铜资源量150万t,Cu平均品位0. 36%。根据矿床特征分析,为典型的斑岩型铜矿床。矿体深部和边部有较大的增储潜力和找矿空间。

Geological characteristics and prospecting potential of Malasongduo copper deposit,Tibet

Malasongduo copper deposit is located in the east of Tibet and is located in the famous Southwest Sanjiang metallogenic belt.The outcrop strata are acidic volcanic rocks of lower Triassic malasongduo Fm. (T₁m) and upper Triassic jiapila Fm. (T₃j) clastic sedimentary rocks.The mining area is located at the core of the anticline.There are three biotite monzogranitic porphyry bodies in the mining area, which are high potassium calc-alkaline series - potassium basalt series, and the isotopic age (K-Ar method) is 34.6 ~ 40.8Ma, belonging to the early products of Xishan.The area is characterized by surface alteration, and the zones from the center to the edge are potassium silicification zone-sericitization zone- hornization zone-qingpan lithalization zone.The Angkenong rock mass has been mineralized into a ore body with an elliptic plane, about 950m long and 800m wide.The section is irregularly columnar with an average vertical thickness of 315m.The copper resources of ore body are 1.5 million tons and the average grade of Cu is 0.36%. According to the analysis of the deposit characteristics, it is a typical porphyry copper deposit.The depth and the edge of the ore body have great potential of increasing storage and prospecting.