New paleomagnetic results from the Yangzhuang Formation of the Jixian System,North China,and tectonic implications

作     者：WU Huaichun ZHANG Shihong LI Zheng-Xiang LI Haiyan DONG Jin 

作者机构：State Key Laboratory of Geological Processes and Mineral Resources & Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China Tectonics Special Research Centre School of Earth and Geographical Sciences The University of Western Australia Crawley WA 6009 Australia 

出 版 物：《Chinese Science Bulletin》 (中国科学通报)

年 卷 期：2005年第50卷第14期

页      面：1483-1489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] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.40032010-B) 

主　　题：古磁学 中元古代 中国 岩石 

摘      要：A paleomagnetic study was carried out on the Yangzhuang Formation (~1350 Ma) of the Jixian System in the North China Block (NCB). Detailed stepwise thermal demagnetization isolated two components. The soft compo- nent (component A) was interpreted as a remagnetization in the recent geomagnetic field. The hard component (compo- nent B) with higher unblocking-temperatures was carried by hematite. Its site-mean direction is D/I = 77.6°/-24.3° (κ = 5.4, α95 = 18.3°, N = 15 sites) before, and D/I = 72.2°/11.5° (κ = 24.6, α95 = 7.9°) after tilt correction. It passes a fold test (Mesozoic folding) at 99% confidence level and reversal test at 95% confidence level. The corresponding pole locates at 17.3°N, 214.5°E (dp = 4.1°, dm = 8.0°). A best fit of paleo- magnetic poles from the NCB, Baltica, Siberia and the ap- parent polar wander path for Laurentia suggests a long-lived connection between these paleo-continents between ~1800 and 1350 Ma.