The fluvio-lacustrine sequence of the Shanwang Basin,eastern China,preserves a rich and important terrestrial ...
Huaiyu He~(a,*),Chenglong Deng~b,Yongxin Pan~a,Tao Deng~c,Zhaohua Luo~d,Jimin Sunb,Rixiang Zhu~b a Key Laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China b State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China c Institute of Vertebrate Paleontology and Paleoanthropology,Chinese Academy of Sciences,Beijing 100044,China d China University of Geosciences,Beijing 100083,China
Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in ...
ZHAO XiangYu~(1,2) & LIU QingSong~(1*) 1 Paleomagnetism and Geochronology Laboratory(SKL-LE),Institute of Geology and Geophysics,Chinese Academy of Sciences, Beijing 100029,China
Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out closely following the guidance of cathodoluminescence images, and the majority of analyses were conducted on the oscillatory zircon grains. Thirteen measurements yield a highly reliable Concordia U-Pb age of 536.7 ± 3.9 Ma for the Bed 5 horizon. A grand mean of 206Pb/238U age of 535.2± 1.7 Ma (MSWD = 0.53) is calculated based on 13 concordant SIMS measurements of this study and 4 nano-SIMS measurements of Sawaki et al., which is the best estimate of the deposition age of the tuff layer within Bed 5 in the Meishucun section. This age has provided a robust age constraint on the significant Precambrian-Cambrian boundary strata in southern China, which independently suggested the placement of the Precambrian-Cambrian boundary at the bottom of the Xiaowaitoushan Member (Marker A).
RiXiang Zhu XianHua Li XianGuang Hou YongXin Pan Fei Wang ChengLong DengHuaiYu He
