Geochemistry and Zircon U-Pb Geochronology of Early Paleozoic S-type Granites in the Eastern Qilian Block,Northwest China

• 作者: LIU Xiuting LI Binkai HAN Jilong REN Erfeng GAO Donglin DU Yongsheng REN Qianhui ZHANG Yan
• 来源期刊: 地质学报（英文版）
• 年，卷（期）: 2021,（2）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 439-458
• 页数: 20页
• 语种: 英文

摘要

The Qilian Block(QB)is a Precambrian micro-continent located in the northeastern Qinghai-Tibet Plateau.Prevalent Lower Paleozoic granitic magmatic rocks crop out in the QB.A new integrated study of zircon U-Pb ages and systematic whole-rock geochemical data for the Xindian,Dongjiazhuang and Xiaogaoling granites in the eastern segment of the QB constrains their emplacement ages,petrogenesis,and regional evolutionary history.U-Pb dating reveals that the Xindian granite was emplaced 454 Ma,and both the Dongjiazhuang and Xiaogaoling granites were emplaced ca.440 Ma.Geochemical study shows that all granites belong to the high-K calc-alkaline to shoshonitic series and are S-type granites formed by partial melting of continental crust,mainly metagraywacke.We infer that these ca.454-445 Ma granites formed in a syn-collisional setting during the continental collisional between the Qaidam and Qilian blocks.