Identification of 3.5 Ga detrital zircons from Yangtze craton in south China and the implication for Archean crust evolu
The LA-ICP-MS U-Pb dating of hundreds of detrital zircon grains from the Sinian sandstones of Liantuo formation and tillites of Nantuo formation at Sanxia area in Yichang identified 3319-3508 Ma zircon grains. Their 207pb/206pb and 206pb/238U ages show excellent agreement (concordia degree 99 %-100 % ). Their CL images exhibit well-developed oscillatory zoning and the Th/U ratios are within 0. 46-0. 76, implying that they are igneous zircons which formed during middle-early Archean. These zircons are the oldest ones discovered in Yangtze craton until now. However, the detrital zircons with ages older than 3.3 Ga in the metamorphic rocks of Kongling group were not found by further investigation, which suggests the presence of crust older than high-grade metamorphic Kongling terrain in Yangtze craton.
作 者： LIU Xiaoming GAO Shan LING Wenli YUAN Honglin HU Zhaochu 作者单位： LIU Xiaoming,GAO Shan(National Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China;Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China)LING Wenli(National Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China)
YUAN Honglin,HU Zhaochu(Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China)
刊 名： 自然科学进展（英文版） SCI 英文刊名： PROGRESS IN NATURAL SCIENCE 年，卷(期)： 2006 16(6) 分类号： N1 关键词： early Archean detrital zircon zircon dating Yangtze craton