蒙古国东南部钨多金属靶区的快速圈定与成矿分析

Rapid Determination of a Tungsten Polymetallic Target in Southeast Mongolia and Metallogenic Analysis

复杂地表条件下矿产勘探一直是个难题,国外区块更是如此,首次利用XLT-592WZ型便携式XRF分析仪在蒙古国苏赫巴托尔省(额尔德尼查干苏木)13451X草原覆盖地区系统采集数据,分析研究并圈定成矿靶区。初期利用X荧光仪进行扫面勘探,发现有W、As、Pb、Zn、Cu、Fe等元素异常,经过异常查证优选了一个钨多金属找矿远景区。在钨多金属找矿远景区内通过23条探槽和钻探工程进一步揭露发现一条黑钨矿体;钨矿主要以脉状、团块状或是角砾状形式出现,成矿围岩为花岗斑岩,矿石以黑钨矿为主,白钨矿极少,可见硅化、萤石,推测该区成矿类型为高温热液型黑钨矿。综合来看,在野外利用便携式X荧光光谱仪进行定性与半定量分析是有效的,该方法可在同类地区推广应用。

The mineral exploration in complex surface conditions has always been a difficult problem in China so as in foreign exploration blocks. The exploration area 13451X is a thick cover grassland located in Sukhbaatar Province of Mongolia. In this work, for the first time we used the XLT-592WZ hand-held X fluorescence spectrometer to collect data in the field, and determined a metallogenic target area. The early scanning exploration using X-ray fluorescence identified the W, As, Pb, Zn, Cu and Fe anomalies, and geochemical surveys delineate a tungsten polymetallic ore-prospecting area. Twenty-threetrenches and drilling projects suggest a tungsten ore body in the ore-prospecting area. This tungsten orebody mainly appears in veiny, blocks or brecciated form, and its surrounding rock is granite porphyry or quartz porphyry. The ores are dominated by wolframite with trace of scheelite, and silicification and fluorite can be found. It is thus inferred that this deposit is of the high-temperature hydrothermal type. We can conclude that the use of portable X-ray fluorescence spectrometer for qualitative and semi-quantitative analysis in the field is effective, and that this method can be widely applied in similar areas.