投稿时间:2014-04-19
修订日期:2014-12-03
网络发布日期:2015-05-06
中文摘要:多龙矿集区位于班公湖-怒江成矿带西段、羌塘地块南缘的岩浆弧中。过去十多年来, 西藏地勘局第五地质大队在多龙矿集区内已发现和评价了多不杂、波龙、地堡那木岗、拿若、荣那等5处大型、超大型铜金多金属矿床, 目前已探明的铜资源量近1000万吨, 金300余吨。区内以斑岩型铜金矿床为主, 兼有斑岩-浅成低温热液型和斑岩-角砾岩型矿化组合。研究发现, 矿区黄铁矿的δ34S值变化于-2.2‰~2.3‰之间, 平均为0.2‰, 峰值在-1‰~1‰之间, 塔式效应明显, 接近幔源硫, 显示成矿物质来源于深部岩浆;成矿温度介于250~420℃之间, 成矿深度1~5 km, 成矿流体为残余岩浆流体, 大气降水在成矿过程中的作用不明显。作者根据多年的勘查实践, 总结出多龙矿集区斑岩型铜金矿最有效的找矿勘查方法技术组合是:地质+化探(水系沉积物)+物探(高精度磁测、激电中梯)+钻探。
Abstract:The Duolong copper ore concentration area occurs in the western segment of Bangong Co-Nujiang suture zone and is located in the magmatic arc on the southern margin of Qiangtang block. In the past more than ten years, No. 5 Geological Party from the Tibet Bureau of Geology and Exploration found and evaluated five large and superlarge gold-copper polymetallic deposits in the ore concentration area, namely Duobuza, Bolong, Dibaonamugang, Naruo and Rongna. The proved copper and gold reserves have reached nearly 10 million tons and more than 300 tons, respectively. The ore deposits are mainly porphyry-type copper-gold deposits, with some epithermal and breccia type deposits. The investigation indicates that the δ34S values of the rocks in the orefield vary from -2.2‰ to 2.3‰ with an average of 0.2‰, and the peak value ranges from -1‰ to 1‰, exhibiting tower distribution in the sulfur isotopic histogram of δ34S, which is similar to the mantle-sourced sulfur isotope. These phenomena indicate that the ore-forming materials were mainly derived from deep magma. The ore-forming temperature ranges from 250℃ to 420℃ and the depth changes from 1 km to 5 km. The ore-forming fluid mainly originated from residual magmatic fluid, whereas the role of the meteoric water was insignificant. Based on years of exploration practice, the authors finally established the most effective prospecting- exploration technical combination for the Duolong ore concentration area, that is, geology + geochemical exploration(stream-sediments)+geophysical exploration (high-precision magnetic+IP intermediate gradient)+drilling.
keywords:geology porphyry copper-gold deposit Duolong copper ore concentration area genetic model comprehensive prospecting model Bangong Co-Nujiang metallogenic belt Tibetan Plateau
文章编号:
中图分类号:P618.41;P618.51
文献标志码:
基金项目:本文得到中国地质调查局青藏专项"西藏班公湖-怒江成矿带中段铜矿评价调查"(编号:12120113037300)项目资助
引用文本:
陈红旗,曲晓明,范淑芳.2015.西藏改则县多龙矿集区斑岩型铜金矿床的地质特征与成矿-找矿模型[J].矿床地质,34(2):321~332CHEN HongQi,QU XiaoMing,FAN ShuFang.2015.Geological characteristics and metallogenic-prospecting model of Duolong porphyry copper-gold ore concentration area in Gerze County, Tibet[J].Mineral Deposits34(2):321~332
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