Geochemical and ⁴⁰Ar-³⁹Ar Isotope Chronological Characteristics of Wugongshan Indo-Chinese Granites in Central Qiangtang, Tibetan Plateau

详细信息   

• 责任者：Hu Peiyuan (College of Earth Science ; Jilin University ; Changchun 130061 ; China) ; Li Cai
• 刊名：Geological Bulletin of China
• 出版年：2012
• 卷期：31（6）
• 关键词：花岗质片麻岩 ; granitic gneiss ; 二长花岗岩 ; monzogranite ; 青藏高原 ; Qinghai-Tibetan Plateau
• 页码：p.843-851
• 图表：5 illus., 4 tables, 18 refs.
• 分类号：0801
• issnNo：ISSN1671-2552
• isbnNo：CN11-4648/P

摘要

///Bensongcuo batholith occupies an area of over 1 800 km² and is the greatest granite multiple batholith in central Qiangtang. Geochemical studies indicate that monzogranites are high-potassium peraluminous calc-alkaline granites formed in collisional tectonic setting, similar to other Indosinian intermediated-acid rocks in this area. The intermediated-acid rocks compose the collisional or post-collisional magmatic arc of the Lungmu Co-Shuanghu-Lancang River suture zone. Moreover, ⁴⁰Ar-³⁹Ar dating was carried out for biotites from the granite gneiss and the dating results show that the granitic gneiss resulted from the reformation of Indo-Chinese granites by Jurassic magmatism at (175.8±1.1) Ma, and hence the Bensongcuo batholith should serve as the material record of multi-stage intrusion of intermediate-acid magmatic rocks.oft-com:office:office" />