U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the te
The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the Beijing Ion-probe Center, acquire 206Pb/238U ages of 368±3.5 Ma (of granite, 95% confidence level, MSDW=1.23) and 362.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04) respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep thermal-dynamic process when the Gondwana continent began to break up in the Devonian period.
作 者： DING Shijiang HU Jianmin SONG Biao CHEN Mulun XIE Shengzhou FAN Yuan 作者单位： DING Shijiang,CHEN Mulun,XIE Shengzhou,FAN Yuan(Geological Surveying Institute of Hainan, Haikou 570206, China)HU Jianmin(Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China)
SONG Biao(Beijing Center of SHRIMP, Beijing 100037, China;Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China)
刊 名： 中国科学D辑（英文版） SCI 英文刊名： SCIENCE IN CHINA (EARTH SCIENCES) 年，卷(期)： 2005 48(12) 分类号： P5 关键词： Hainan Island Devonian period anatectic granite zircon SHRIMP U-Pb dating