西峰蔡家咀黄土剖面记录的末次盛冰期到全新世最佳期气候变化

Climatic Change from LGM to Holocene Optimum Recorded by Loess Sequence from Xifeng in Central Loess Plateau

采用挖探井方式获取西峰蔡家咀剖面200 cm黄土沉积序列,以7个14C-AMS测年数据为年龄控制点,利用沉积物粒度模式建立最近20 ka的年代框架。磁化率、灰度、粒度等指标的综合对比表明该剖面记录了末次盛冰期增温以来几次重要气候事件,如Heinrich事件1(H1)、Blling-Allerd暖期(B-A)、新仙女木事件(YD)、8.2 ka事件等,说明西峰黄土剖面具有记录短尺度气候突变事件的潜力。

A 200-cm long successive loess core was firstly obtainded by diging a well at Caijiazui section in the Xifeng located in central loess Plateau in China.According to 14C-AMS dating results and the grain size model,the reliable chronologic framework of Xifeng section over the past 20 ka was derived in turn.Multi-proxy analysis on the magnetic susceptibility,grey scale and grain size clearly reveal the typical climatic episodes such as Heinrich 1（H1）,Blling-Allerd（B-A）,Younger Dryas（YD）,and 8.2 ka event.It suggests the potential ability of Xifeng loess section for recording the abrupt climatic variations on the small scale.