Determination and genesis of“magnesian skarn”or“ultramafite”of Galale Cu-Au deposit in Tibet,China
Author(s): ZHANGZhi, TANGJu-xing, WANGLi-qiang, YAOXiao-feng, WANG Hong-xing, SONGJun-long, YANGYi, HUZheng-hua, College of Earth Sciences, Chengdu University of Technology, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Development Research Center of China Geological Survey
Pages: 159-168
Year: 2015 Issue: 2
Journal: Journal of Chengdu University of Technology
Keyword: magnesian skarn; ultramafite rock; genesis; Tibet;
Abstract: The Galale copper-gold deposit is the typical deposit of the collisional mineralization events on the southern margin of the Bangonghu-Nujiang metallogenic belt in Tibet.Its gold resources has reaches more than that of a large-scale deposit.In view of the differences in exploring theory and prospecting direction led to by the different views on the genesis of the deposit in exploring deposits,this paper gives emphasis to studying the characteristics of petrology and geochemistry based on thedetermination of the"magnesian skarn"and"ultramafite rock".The research result shows that there are obvious characteristics of dual contact metasomatism among the "ultramafite rock"and dolomite and granodiorite in the aspect of the major elements.Trace elements show the characteristics of having Ba,K,Ti negative anomalies,enriching Rb,U,Th etc.,and losing Hf,Ti of high field strength elements;REE shows that LREE and HREE fractionation is obvious and the LREE is apparent tilt partition.Trace elements and REE geochemical characteristics are seriously inconsistent with that of the ultramafite rock related to ophiolite regionally.On the contrary,trace elements and REE have a close affinity and inherited characteristics with dolomite and granodiorite. The comprehensive studies show that the previous so-called"ultramafite rock"is the contact metasomatic"magnesian skarn",and the deposit is the contact metasomatic copper-gold skarn deposit.
Pages: 159-168
Year: 2015 Issue: 2
Journal: Journal of Chengdu University of Technology
Keyword: magnesian skarn; ultramafite rock; genesis; Tibet;
Abstract: The Galale copper-gold deposit is the typical deposit of the collisional mineralization events on the southern margin of the Bangonghu-Nujiang metallogenic belt in Tibet.Its gold resources has reaches more than that of a large-scale deposit.In view of the differences in exploring theory and prospecting direction led to by the different views on the genesis of the deposit in exploring deposits,this paper gives emphasis to studying the characteristics of petrology and geochemistry based on thedetermination of the"magnesian skarn"and"ultramafite rock".The research result shows that there are obvious characteristics of dual contact metasomatism among the "ultramafite rock"and dolomite and granodiorite in the aspect of the major elements.Trace elements show the characteristics of having Ba,K,Ti negative anomalies,enriching Rb,U,Th etc.,and losing Hf,Ti of high field strength elements;REE shows that LREE and HREE fractionation is obvious and the LREE is apparent tilt partition.Trace elements and REE geochemical characteristics are seriously inconsistent with that of the ultramafite rock related to ophiolite regionally.On the contrary,trace elements and REE have a close affinity and inherited characteristics with dolomite and granodiorite. The comprehensive studies show that the previous so-called"ultramafite rock"is the contact metasomatic"magnesian skarn",and the deposit is the contact metasomatic copper-gold skarn deposit.
Related Articles