High-precision uranium-series dating of lacustrine carbonates from Daihai Lake  

作　　者：SUN Qianli ZHOU Jie PENG Zicheng LIU Weiguo Xiao Jule 

机构地区：[1]Institute of Earth environment,Chinese Academy of Sciences,Xi’an 710054,China [2]Department of Earth and Space Science,University of Science and Technology of China,Hefei 230006,China [3]Institute of Geology&Geophysics,Chinese Academy of Sciences,Beijing 100029,China

出　　处：《Chinese Science Bulletin》2001年第7期588-591,共4页

基　　金：the National Key BasicResearch Development Project (Grant No. 1999043401); the Key Project of Knowledge Innovation of the CAS (Grant No. KZCX1-Y-05); the Key Project of the CAS (Grant Nos. KZ952-J1-015 and KZ-951-A1-402) ;and the National Outstandin

摘　　要：Ages of small aragonite samples retrieved from sediments from the Daihai Lake are determined by using the Thermal Ionization Mass Spectrometry (TIMS) technique. The ages of the samples range from (8740±601) to (10446±489) a, with a precision of 2%-3% for non-corrected dating ages and 4.7%-9.8% for corrected ages respectively, and are consistent within the deviation range. At about 10.5 ka BP, the grain-size of the sediments coarsens sharply, the frequency curves of grain-size distribution show coarse grain dominated single-double kurtosis, indicating cooling, decreased hydrodynamic conditions and increased wind influence procedure. This is in good agreement with previous results obtained from the Daihai Lake, which suggests that the climate was cold and the lake surface was shrinking. The TIMS ages of the sediments are therefore believed to be credible.Ages of small aragonite samples retrieved from sediments from the Daihai Lake are determined by using the Thermal Ionization Mass Spectrometry (TIMS) technique. The ages of the samples range from (8740±601) to (10446 ±489) a, with a precision of 2%–3% for non-corrected dating ages and 4.7%-9.8% for corrected ages respectively, and are consistent within the deviation range. At about 10.5 ka BP, the grain-size of the sediments coarsens sharply, the frequency curves of grain-size distribution show coarse grain dominated single-double kurtosis, indicating cooling, decreased hydrodynamic conditions and increased wind influence procedure. This is in good agreement with previous results obtained from the Daihai Lake, which suggests that the climate was cold and the lake surface was shrinking. The TIMS ages of the sediments are therefore believed to be credible.

关 键 词：Daihai LAKE Thermal IONIZATION MASS SPECTROMETRY aragonite. 

分 类 号：P597[天文地球—地球化学]