Petrology, Geochemistry and Protolith of the Biotite Plagiogneiss from Hongqiyingzi Group in Chicheng County, Northern Hebei Province

详细信息   

• 责任者：Zhang Jing (College of Earth Sciences ; Chengdu University of Technology ; Chengdu 610059 ; China) ; Ni Zhiyao
• 刊名：Acta Petrologica et Mineralogica
• 出版年：2012
• 卷期：31(3)
• 关键词：黑云母片麻岩 ; biotite gneiss ; 岩石地球化学 ; lithogeochemistry ; 河北 ; Hebei Province
• 页码：p.307-322
• 图表：11 illus., 3 tables, 27 refs.
• 分类号：0802
• issnNo：ISSN1000-6524
• isbnNo：CN11-1966/P

摘要

///Biotite plagiogneiss samples from Hongqiyingzi Group in Chicheng County of northern Hebei Province have porphyroblastic texture with medium-fine grained lepido-granoblastic groundmass and gneissic structure. Blastopsammitic texture is preserved locally. The rocks mainly consist of plagioclase （28%～32%), quartz （35 % ～ 40%） and biotite (18 %～25%), with minor garnet (2%～8%, as porphyroblast） and graphite （1%～4%).  Garnet compositional characteristics reveal that the temperature and pressure fell contemporaneously during the main metamorphic evolution. The geochemical characteristics of the biotite plagiogneiss samples from Hongqiyingzi Group suggest that their protolith might have been pelitic （or pelitic-bearing） sandstone and was formed in a tectonic environment similar to the continental island arc.