Geochemical Features and Tectonic Setting of the Laohegou Granite and the Shaiziyan Granite in Bikou Block, in Northwest Sichuan Province

• 责任者：Li Zuochen (Key Laboratory of Western China’s Mineral Resources and Geological Engineering ; Ministry of Education ; Faculty of Earth Science and Resources ; Chang’an University ; Xi’an 710054 ; China) ; Pei Xianzhi
• 刊名：Acta Geologica Sinica
• 出版年：2010
• 卷期：84(3)
• 关键词：花岗岩 ; granite ; 构造环境 ; tectonic setting ; 四川 ; Sichuan Province
• 页码：p.343-356
• 图表：12 illus., 1 table, 107 refs.
• 分类号：0801
• issnNo：ISSN0001-5717
• isbnNo：CN11-1951/P

The Louhegou granite and the Shaiziyan granite are located in southern margin of Bikou block. The data of occurrence, petrography and geochemical are reported, the source and tectonic setting of the granite are discussed in this paper. The results show that the Louhegou granite and the Shaiziyan granite have high SiO₂ (69.89% ~ 71.69%), and Al₂O₃ composition, A/CNK = 1.4~1.12. These rocks are post-orogenic granite, and are typical crust source petrogenesis. These granites mass are interpreted as a kind of syn-collisional granites resulted from the crustal thickening caused by the collision between the North China massif and Yangtze massif during the Indosinian. These rocks were transitional environment of compressional orogeny and extensional structure.