对取自泥河湾盆地东部化稍营镇(114°36’E,40°18’N)附近一剖面以泥炭为主的沉积物做了AMS 14C测年、粒度、碳酸钙含量、碳酸盐中δ18O和δ13C组分、有机质含量、TOC、CN分析以及χlf和SIRM测量。结果表明,这些沉积物大致是在5320～3370 a B.P.堆积的;在5320～3600 a B.P.,气候仍较为湿润温暖;在3600～3460 a B.P.和3430～3400 a B.P.,有两次明显的干冷干事件。气候的这种波动,可能是中全新世湿润状况的结束过程。
AMS 14C dating, analyses of grain-size, CaCO3 content, δ18O and δ13C in carbonates, content of organic matter, TOC content and C/N ratio, and measurements of χlf and SIRM are performed with sediments, consisting mainly of peat, from a profile near Huashaoying Town (114°36’E, 40°18’N), the eastern part of Nihewan Basin. The results indicate that these sediments were deposited mainly during 5320-3370 a B.P.; the climate was still rather humid and warm during 5320-3600 a B.P.; there was a marked dry/cold-and-dry event occurring respectively at 3600-3460 a B.P. and 3430-3400 a B.P. Such climatic fluctuations might be the terminating process of the mid-Holocene wet conditions.
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