Discovery and Significance of Beimulang Porphyry Cu-Mo Deposit,Xizang
Ci Qiong
Zheng Youye
Wu Song
Liu Peng
Zhao Yayun
Gong Fuzhi
Du Zezhong
Hou Yitao
Abstract：The Zhunuo ore concentration district is located in the western Gangdese metallogenic belt,Xizang.The area contains a large NE-SW geochemistry anomaly,which exhibits favorable metallogenic conditions and is a key block for the deployment of a new round of breakthrough strategic actions in mineral exploration.The Beimulang deposit is a newly discovered porphyry Cu-Mo deposit after the Zhunuo deposit in the area.Beimulang contains a mental reserve of 1.3 million tons averaging 0.51％Cu.Magmatic activity in the deposit is strong,including pre-mineralization quartz porphyry(～49.7 Ma),inter-mineralization monzogranite porphyry(～14.8-14.0 Ma),monzogranite(～14.1 Ma),diorite porphyry,and late-mineralization granite porphyry(～11.0-11.7 Ma),lamprophyre.Mineralization occurs mainly in the main inter-mineralization and pre-mineralization intrusions.Molybdenite Re-Os dating shows that main-stage mineralization at Beimulang formed in 13.8±0.1 Ma.Three breccia types have been observed in the deposit,typically located in the apical parts of monzogranite porphyry:(1)tourmaline-cemented breccia,(2)clast-supported breccia,and(3)quartz-pyrite-cemented breccia.Hydrothermal alteration is strongly developed and includes central potassic,peripheral propylitic,and shallow phyllic alteration.The three kinds of alteration are superimposed on each other.Biotite alteration is most closely associated with Cu mineralization.The discovery of the Beimulang deposit confirms the prevailing view that large and super-large porphyry Cu deposits can be formed in areas that cannot be formed or have low ore-forming potential,which provides a new example for further study of the porphyry mineralization process and deep metallogenic mechanism in collision orogenic belt.The discovery of the Beimulang Cu-Mo deposit is attributed to the demonstration of comprehensive exploration methods such as geology,stream sediment geochemical,and hyperspectral analysis.In particular,short-wave infrared spectroscopy technology can effectively trace hydrothermal/mineralization centers.The discovery of the deposit has pointed out the direction for searching for similar deposits in the region and also provided important support for the Zhunuo ore concentration district to become another new ten million tons of copper resource base in China.
Keywords：alteration-mineralizationhyperspectralporphyry copper depositBeimulangXizangmineral deposits
Publication Date：2025-04-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：14( 1305-1318 )