The Deqin Yangla Of Copper Deposits In The Geological And Metallogenic Prediction

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.