云南德钦羊拉铜矿的矿床地质及成矿预测

【作者】 胡光龙；

【导师】 秦德先； 姚志华；

【作者基本信息】 昆明理工大学 ， 矿产普查与勘探， 2008， 硕士

【摘要】 羊拉铜矿集中区位于滇西北的德钦县羊拉乡,构造上位于我国西南“三江”中段的金沙江接合带,夹持在金沙江断裂和羊拉断裂两条南北向大断裂之间。羊拉铜矿区由七个矿段组成,矿化带北起贝吾,南至加仁,全长约25km,宽5.5—7km,呈近南北向展布,本次研究、勘查主要矿段由北至南依次为江边矿段、里农矿段及路农矿段。里农矿段分布于里农复式岩体西侧岩体边部及里农组(D₂₊₃l)、江边组（D₁j）围岩之中。矿（段）由密集的层状及大脉状矿体（层）组成。路农矿段分布于加仁岩体北东侧外接触带具矽卡岩化的江边组中段（D₁j²）。江边矿段分布于里农、江边复式岩体东、北侧内、外接触带。矿体严格受地层、岩体和构造破碎带控制,呈层状、似层状、透镜状、脉状产出。含矿岩石以透辉矽卡岩、石榴石矽卡岩为主,次为角岩化变质石英砂岩、绢云砂质板岩、爆破角砾岩、花岗闪长岩。矿床主成矿类型为斑岩一矽卡岩型铜矿床。矿体中组成黄铜矿、黄铁矿的硫以幔源硫为主,有围岩硫加入,成矿温度为300～460℃。成矿物质主要来源于深部地幔,岩浆期后气成—热液在扩散过程中,萃取围岩中矿物成分,形成富矿热液并交代大理岩成矿,主成矿期与岩体侵位同属印支—燕山期,矿床成因较为复杂,初步认为矿床经历了火山沉积盆地热水沉积初始成矿——斑岩～矽卡岩主导成矿——后期构造热液叠加成矿的复杂而漫长的成矿过程。矿体一般分布在印支—燕山期中酸性岩体内、外接触带、岩体内破碎或裂隙带,也可产于围岩中的矽卡岩带内。含矿岩性为泥盆系江边组（D₁j）、里农组(D₂₊₃l)含有角闪安山岩、闪长玢岩的碎屑岩—碳酸盐岩组合。矿化蚀变带、地面磁测中表现出高的磁异常、含矿地段出现铜、锡、金、银、铅、锌、砷、锑等综合化探异常、地表褐铁矿化等为矿区的找矿标志。铜的氧化矿物蓝铜矿、孔雀石是矿区直接的找矿标志。羊拉矿区具有良好的找矿远景,下一步找矿重点应主要放在里农矿段与路农矿段接合部、江边矿段北延、以及外围的贝吾、尼吕、通吉格、加仁等矿段及格亚顶、曲隆等地区。更多还原

【Abstract】 Region of Yangla copper mine is located in Yangla township of Deqin County,the northwest of Yunnan province.Tectonic region of Yangla copper deposit locate in the Jinsha River joint zone of "Sanjiang" middle section,gripped in between the Jinsha River fractures and Yangla fracture,the twe fractures trend north-south.Yangla copper deposit zone is composed of seven ore segments,from the north Beiwu ore segment to the south Jiaren ore segment.It is length approximately 25 km and width 5.5-7km.its strike is almost north-south trending.The objects of research are,form north to south,Jiangbian ore segment,Linong ore segment and Lunong ore segment about the paper.Linong ore segment distribute the west side of Linong ditrigonal rock bodies,in wall rock of Linong group(D₂₊₃l)and Jiangbian group（D₁ j）.Linong ore segment is composed of tight bed and vein ore badies.Lunong ore segment distribute contact zone of the north side of Jiaren rock bady.Jiaren rock bady is belong to contact zone of skarn lithification in middle segment of Jiangbian group（D₁ j²）.Jiangbian ore segment distribute inner and outer contcct zone of eastnorth side of Linong and Jiangbian ditrigonal rock bodies.Ore badies are absolutely controled by stratum,rock badies and tectonic fracture zone. The attitude of ore badies is layered,stratoid,lenticular and vein.ore-bearing rock are main diopside-skarn and granat-skarn,posterior homfels metamorphic quartz sandstone, sericite arenaceous slate,explosive breccia and granodiorite.Metallogenic main types is porphyry- skam copper deposits.Sulfur of chalcopyrite and pyrite in orebodies is mainly the mantle sulfur,at the same time,contain a lttle of sulfur of wall rock.,the mineralization temperature is 300～460℃.Origins of metallogenic materials come from mianly deep mantle.Post-magmatic is diffusion process of gas-hydrotherm.In diffusion the process,gas- hydrotherm extract mineral component of wall rock,form enrichment mineral hydrotherm and mineralize by metasomatism marble. Mineralization period and pluton emplacement belong to Indosinian -Yanshan era.It is preliminarily think the deposit go through initiatory ore-forming process of volcanic sedimentary basins hydrothermal sediment—dominant ore-forming process of porphyry～skarn—ore-forming process of post-structural hydrotherm reformation.this is a far-flung and complex process. Orebodies generally distribute inner and outer incontact zone,fracture zone and overbreak zone of Indosinian-Yanshan era intermediate and acid intrusive bodies. Orebodies occurs skarn zone of vicinity.Lithology of the ore-bearing is compounding of clastic rock and carbonate.Clastic rock contain andesitic porphyrite and diritic porphyrite of Devonian Jiangbian group（D₁ j）and Linong group（D₁j）.Mineralization alteration zone show high magnetic anomaly by ground magnetic survey.Comprehensive geochemical prospection anomaly is copper,sin,gold,silver,lead,zinc,arsenic,stibium in ore-bearing geological units,surface limonite is ore-prospecting indicators in Yangla copper mine.oxide mineral of copper,chessylite and malachite,,is a direct deposit -prospecting symbol.Yangla copper deposit has great prospect of copper.In the next step,emphases of prospecting should focus on joint between Linong segment and Lunong segemt,the northern of Jiangbian segment and the vicinity of mine,for example Beiwu,Nilv,Tonggeji,Jiaren,Geyading and Qulong areas.更多还原