Sources of Cretaceous Bimodal Volcanic Rocks in the Coastal Region of Southeastern China -- Constrains of the Sr content and its isotopes

作     者：XING Guanfu YANG Zhuliang and TAO Kuiyuan Nanjing Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences,534 East Zhongshan Road, Nanjing 210016 

作者机构：Chinese Acad Geol Sci Nanjing Inst Geol & Mineral Resources Nanjing 210016 Peoples R China 

出 版 物：《Acta Geologica Sinica(English Edition)》 (地质学报（英文版）)

年 卷 期：1999年第73卷第1期

页      面：84-92页

核心收录：

学科分类：0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学] 

主　　题：Sr content and its isotopes Cretaceous bimodal volcanics coastal region of southeastern China 

摘      要：Cretaceous volcanism in the coastal region of southeastern China was characteristized by occurrenceof bimodal volcanics consisting of basalts and rhyolites, the geneses of which are still controversial. Based on the factthat their isotopic compositions are similar but the Sr content of the former is much higher than that of the latter, thispaper discusses the respective sources of the two end-member rocks, and concludes that basalts were derived fromthe subduction-related enriched upper mantle wedge and their isotopic compositions had not been affected by crustalassimilation, whereas rhyolites were formed by remelting of the old metamorphic basement, but they were mixed upwith the underplating basaltic magmas to various degrees so that their Sr isotopic compositions varied significantlyfrom the sources and tended to be homogeneous to the latter.