青年科学基金项目开展了河西走廊花海及邻区晚第四纪湖泊演化的年代学研究。结果表明，14C和OSL等测年技术不同可能是导致认识晚更新世高湖面年代学差异的主要原因；湖泊沉积物14C年龄碳库效应存在时空差异。该项目资助在Quaternary Research，Quaternary International，Quaternary Geochronology以及The Holocene等国际SCI刊物上发表6篇论文（其中5篇的第一作者或通讯作者是项目申请人）。针对青年科学基金项目的研究结果以及其它湖区的前期工作，申请项目拟选择两个湖泊（即猪野泽和察尔汗）开展较老地层（>30 kaBP）的14C和OSL测年技术的对比研究，以期进一步揭示青藏高原及邻区晚更新世高湖面年代学存在差异的原因；另外，拟以纳木错和当惹雍错的沉积物岩芯进行利用OSL测年技术校正湖泊钻孔沉积物14C年龄碳库效应时空变化的可行性研究。

The prior project (grant 40901014) focused on the timings of the evolution of Huahai Lake during the late Quaternary. Six papers supported by this project have been published in international SCI journals. As first-author or corresponding-author, the applicant led five of these publications. The main results suggested that (1) inconsistent chronology of lake highstands in different lakes was possibly caused by the difference in dating techniques (e.g. 14C dating or OSL dating), and (2) the reservoir effects of 14C ages varied spatially and temporally in different lakes and sometimes even in the same lake. As OSL results are assessed and thus considered to be reliable, the inconsistence between OSL and 14C chronologies for the same sediment sequence (older than 30 ka BP) could be attributed to the underestimation of radiocarbon dating. In order to further seek the phenomenon of disagreement results of 14C dating or OSL dating for the relatively old strata (>30 ka BP) and its mechanisms, we propose to select two sets of strata from Zhuye Lake and Qarhan Lake respectively as our study materials for comparison of two kinds of dating techniques. Some preliminary researches have already been done in these three lakes, which are useful for the proposed project. Besides, two cores from Nam Co and Tangra Yum Co have also been obtained already. Based upon these two cores, spatial and temporal variations in radiocarbon reservoir effects of lake sediments are proposed to evaluated and calibrated by the comparison with high resolution OSL dating.