First identification of Miocene high-sulfidation epithermal copper(gold,silver)deposit in western section of Gangdese metallogenic belt
The Gangdese metallogenic belt is an important Cu polymetallic deposit belt in China,with numerous por-phyry Cu polymetallic deposits developed in continental post-collisional extensional setting.The continental vol-canic rock area in northwestern Xizang is considered as an ideal exploration area for searching porphyry-epither-mal Cu-Au deposits.Under the support of New Strategic Action of Ore-prospecting Breakthrough,we newly dis-covered a thick Cu(Au,Ag)ore body with high-grade in the Mangla area of Geji County in Ngari Prefecture,Xi-zang.The first drill hole of MLZK0001 shows an ore thickness of 137 meters with average Cu grade of 0.46％.There are 14 samples with w(Cu)more than 1％,with an average of 1.54％.The current depths of the three drilled holes range from 542 m to 709.9 m,with ongoing continuous mineralization of Cu(Au,Ag).The altered mineral assemblages of Mangla Cu(Au,Ag)deposit show high-sulfidation epithermal system features with vuggy quartz,alunite,kaolinite,dickite,pyrophyllite and others.The metal minerals are mainly enargite,tetrahedrite,chalcopy-rite,and Cu-S binary system minerals such as covellite and digenite.The deep porphyry Cu-Au mineralization and porphyry metallogenic system have not been revealed yet.The Mangla Cu(Au,Ag)deposit is the first(por-phyry?)-high sulfidation epithermal Cu-Au deposit developed in the Miocene continental volcanic rocks in the western section of the Gangdese metallogenic belt so far.The discovery of concealed thick Cu(Au,Ag)ore body indicates that the continental volcanic rock area in northwestern Xizang has great potential for searching porphy-ry-high sulfidation epithermal Cu-Au deposits,which stretched the Gangdese metallogenic belt westward for ap-proximately one thousand kilometers.It also provides a new direction for exploring porphyry-epithermal Cu-Au deposits in Miocene volcanic rocks.
万方数据
维普
