Geochemistry of the Carboniferous Volcanic Rocks of Benbatu Formation in Sonid Youqi, Inner Mongolia and Its Geological Significance
详细信息
- 责任者：Tang Wenhao (Key Laboratory of Orogenic Belts and Crustal Evolution ; MOE ; School of Earth and Space Sciences ; Peking University ; Beijing 100871 ; China) ; Zhang Zhicheng
- 刊名：Acta Scientiarum Naturalium Universitatis Pekinensis
- 出版年：2011
- 卷期：47(2)
- 关键词：玄武岩 ; basalts ; 英安岩 ; dacites ; 内蒙古 ; Inner Mongolia
- 页码：p.321-330
- 图表：3 illus., 4 tables, 47 refs.
- 分类号：0801
- 出版序号：20120157
- issnNo：ISSN0479-8023
- isbnNo：CN11-2442/N
摘要
The Carboniferous volcanic rocks of Benbatu Formation at Chagannuoer in Sonid Youqi, Inner Mongolia, consist of basalts with pillow and massive structure and dacites.The SiO2 content of the volcanic rocks mainly fallen in two ranges 48.20%~51.11% and 64.66%~65.42%, showing a bimodal distribution composition. According to Rb-Sr isochron age, SHRIMP U-Pb zircon dating data and paleontological data, Chagannuoer bimodal volcanic rocks formed in Late Carboniferous, about 313~308 Ma. The characteristics of geochemistry and regional geology suggest that Chagannuoer bimodal volcanic rocks formed in post-collisional extensional setting, so it can be inferred that the Solonker suture zone had ever been closed before Late Carboniferous.