Mineralogy Research Of The Of Lu Bei Mafic-ultramafic Intrusion In The West Part Of East Tianshan, Xinjiang

The East TianShan was one of the most important areas for Cu-Ni deposit,Many geologists had undertaken geological survey in there.There were lots of Cu-Ni diposits,which were located in the East Tianshan,such as Tulaergen,Hulu,Huangshandong,Xiangshan,Huangshan,Huangshanxi Cu-Ni deposit,They were stud ied by lots of geologists.We choose Lubei intrusion as our study area,which lo cated in the west part of the Juluotage belt,north of the KangGuer Fault,becaus e it's a new discovered Cu-Ni deposit,which had few works.The Lubei Cu-Ni deposit was studied by petrology,minerology and geochemistry,and we got such conclusions:1)Three magmatic pulses of the Lubei intrusion have been identified:The fir st pulse formed peridotite;The second pulse formed pyroxene hornblendite;The t hird pulse formed gabbro.Iherzolite,the product of the first magmatic pulse,is th e main host rock for the Cu-Ni ores.2)The source magma of Lubei intrusion is tholeiite,The w?MgO?of the pare ntal magma is 15.25%-17.29%,it belonged to basalt and came from mantle regi on.The diorite came from crust region.3)The Lubei intrusion crystallization temperatures of clinopyroxene were 1000.55-1143.20?.The pyroxene hornblendite crystallization temperatures of ortho pyroxene were about 890.25?;The Lubei intrusion crystallization temperatures of hornblende were 1066.50-1188.57?,the pressures were 0.50Gpa,the oxygen f ugacities?lgfO2?were-9^-6.The diriote crystallization pressures of hornblende w ere 0.33Gpa,the oxygen fugacities?lgfO₂?were-22.9^-21.5.The crystallization te mperatures of plagioclase were about 1051?.