云南打拢锡多金属矿地质特征及找矿前景分析

Geological characteristics of Dalong tin polymetallic deposit in Yunnan and its exploration prospective

打拢锡多金属矿位于西藏-缅甸亚构造域中的保山-镇康地块南段,寒武系上统保山组为主要含矿层位,近SN向的镇康复背斜和NE、NW向共扼断层组成基本构造格架.目前新发现锡矿体14条,长度为70～431.5m,斜深为17.5～137m,水平厚度为0.41～10.09m.矿体平均品位：w（Sn）为0.21×10^-2～1.59×10^-2.矿体产状多与围岩一致,倾向为300°～330°,倾角多为15°～38°.矿体多呈似层状及透镜状,沿走向及倾向具有膨大收缩、尖灭再现特点.初步研究认为,NE向构造和寒武纪地层控制着以锡为主的多金属矿空间展布,且与物、化探异常相吻合.区域上有与之类似的地质条件和综合物化探异常区多处,找矿潜力巨大.因此,若适当增加地勘投入,本区有望成为中-大型锡多金属矿勘查基地.

The Dalong tin polymetallic deposit is located in south part of Baoshan-Zhenkang massif in Tibet-Burma subtectonic domain. The major ore bearing layer is upper Cambrian System. The tectonic framework is consist of near NS-striking Zhenkang anticlinorium, NE and NW striking conjugate faults. Fourteen tin orebodies, 70m～431.5m long, 17.5m～137m dip in trend, and 0. 41m～ 10. 09m thick in horizon, discovered in the study area. And the relative height of outcrops is more than 400m. The occurrence of the orebodies is coincided with country rocks, 300°～330° trending, mostly 15°～38°dipping. The shape of ore body are stratoid or pod-like, which have the feature of swell, shrink, wedge out and reappearance in the direction of striking and dip. The initial study shows that NE trending structures and Cambrian stratra control the spacial extension of tin polymetallic deposits, coincided with physical and geochemical anomalies. There are several spots where is of great potential for prospecting, sharing the similar geological condition and comprehensive geophysical and geochemical anomaly zones having been found in the region. Therefore the area would become a medium to large scale tin polymetallic deposit exploration base if appropriate exploration fund was added.