A debate on the special circumstance of rock-forming and ore-forming of Haladala pluton, a mafic-ultramafic complex related to CuNi-VTiFe composite mineralization, in western Tianshan
西天山CuNi-VTiFe复合型矿化镁铁-超镁铁杂岩 ——哈拉达拉岩体成岩成矿背景特殊性讨论

Haladala pluton,a mafic-ultramafic complex related to CuNi-VTiFe composite mineralization in western Tianshan,consists of troctolite,olivine gabbro,hornblende gabbro and diabase.The SHRIMP zircon U-Pb age of 308.8±1.9Ma,307.3±8.2Ma for olivine gabbro and gabbro of the Pluton were obtained.The major rock types in the Haladala pluton show cumulate texture,gabbro-ophitic textures,and the pluton exhibits well-developed rhythmic layering.All the different types rock of the plutons have rather similar trace-element distribution and REE patterns with positive Eu,Sr abnormity mostly,and it suggests they were the results of crystallization differentiation of the similar or same magma.The geochemical characteristics of Sr-Nd isotope compsition,initial 87Sr/86Sr values=0.703913～0.705259,εNd(t)=4.00～8.42,show that the original magma came from depleted mantle source.The study proposes that the Haladala pluton was formed in an early post-collisional orogenic stage,overlaying the possible mantle plume in the same time.