摘要

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 Sr-87/Sr-86 values = 0.703913 similar to 0.705259, epsilon(Nd)(t) = 4.00 similar to 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.

  • 出版日期2012-7
  • 单位北京矿产地质研究院