Metallogenic environments for mafic-ultramafic Ni-Cu-Co deposits in eastern Tianshen and Beishan,NW-China:Overlapping of Early Permian plume to orogenic Belt
Systematically petrological,mineralogical,geochronlogical and geochemical approaches on the mafic-ultramafic complexes and associated Cu-Ni-Co and V-Ti-Fe deposits in the eastern Tianshan and Beishan regions reveal that those intrusions and their source magmas show bilateral characteristics both of orogenic belt and mantle plume as well as regular regional variations from north to south.Those mafic-ultramafic complexes occurred along ductile shear zone or deep-seated fracture.SIMS analyses of zircon of the regional mafic-ultramafic complexes yields a relatively restricted range of 278.6 Ma to 286.4 Ma (Fig.1).The complexes in both eastern Tianshan and Beishan regions have positive bulk εNd(t) and zircon εHf(t) values,suggesting that their parental magmas were derived from depleted mantle sources.Whereas bulk trace elements and zircon Hf-O isotopes reveal that the depleted mantle sources had been subjected to subduction-related modifications,in which fluid-modification was dominated beneath the Beishan region and both fluid- and melt-modifications occurred beneath the Eastern Tianshan.
Ke-Zhang Qin Ben-Xun Su Dong-Mei Tang He Sun Ya-Jing Mao Sheng-Chao Xue Qing-Hua Xiao
Key laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Science,Beijing 100029,China
国际会议
贵阳
英文
196-199
2012-06-16（万方平台首次上网日期，不代表论文的发表时间）