Late-glacial and Holocene climate change recorded in loess profile in Weibei loess tableland

Field investigations,grain size analysis ,hygroscopic water and magnetic susceptibility measurement in a loess profile of Late glacial and Holocene in Changwu,Shaanxi,have revealed the characteristics of the climate change during late 14700 years. The results show hat the Younger Dryas and Bolling and Allerod short term climatic events are well recorded in the profile. Between 8500～3100 a.BP,Pedogenic process was very strong. A layer of Heilu soil was formed on the Loess tableland. There is a transformation phase between 3400～3100 a.BP. It represents a climate change from the period dominated by Southeastern monsoon to the period dominated by northwestern monsoon. From 3100a.BP soil degradation is remarkable. A layer of Loess has been accumulated since 3100 a.BP, which has the Heilu soil buried. This means the last 3100 years is a dry period with intensified dust accumulation.