The Character and Genesis of Anorthite as Inclusions in Spinel of Mantle Peridotites from the Purang Ophiolite (Southwestern Tibetan Plateau)

详细信息   

• 责任者：Guo Guolin (State Key Laboratory Breeding Base of Nuclear Resources and Environment ; East China Institute of Technology ; Nanchang 330013 ; China) ; Xu Xiangzhen
• 刊名：Acta Petrologica Sinica
• 出版年：2011
• 卷期：27(11)
• 关键词：橄榄岩 ; peridotites ; 尖晶石 ; spinel ; 钙长石 ; anorthite ; 西藏 ; Tibet
• 页码：p.3197-3206
• 图表：5 illus., 3 tables, 32 refs.
• 分类号：0801
• issnNo：ISSN1000-0569
• isbnNo：CN11-1922/P

摘要

The vermicular-shaped anorthite as inclusions in spinel and the subhedral anorthite were both discovered in the mantle peridotites from the Purang ophiolite in Tibet. Research shows that there exists no zoning forms and the An values of anorthite are greater than 95 in these two distinct anorthites, which indicating the rock’s cooling time is short and its forming depth is low. The anorthite inclusions are relatively high in value of Cr₂O₃, and its host mineral spinel is with low Cr# and content of TiO₂ is much lower compared with those in abyssal peridotites. Thus, it might be inferred that both anorthite and spinel have crystallized at the same time.