早全新世石羊河流域沙尘暴活动记录

位于西北干旱区河西走廓东段石羊河流域尾闾地区湖泊沉积中记录到了多层快速风成沉积，通过剖面样品粒度、石英砂表面特征和磁化率、有机碳等多指标的分析表明为沙尘暴的堆积，推断在早全新世10000-6700aB.P.石头号河流域气候最湿润阶段仍存在周期性的沙尘暴活动。

Dust Storm Records in Shiyang River Drainage during Early Holocene

Northwestern China is the region with high frequent dust storms in the world, and the dust storms have been the serious disaster in the region It was firstly discovered that deposit records of dust storm during Early Holocene in the investigation into lake sediments in the Hexi Corridor Yema Lake section located in the terminal area of the Shiyang River Drainage of eastern Hexi Corridor, Northwestern China, recorded rich information of the lake evolution and climatic change since Holocene Many interlayers of rapid aeolian coarse silt and fine sand were documented in between the lacustrine sediment, and were considered as transport and deposit of rapid dust storms Furthermore, analysis of grain size, micro shape of quartz sand, magnetic susceptibility and organic carbon revealed the coarse silt and fine sand layers were same as modern dust storm deposit with rapid short haul transporting trait, but different from active dune sand deposit According to interpolation of the 14 C ages of different depth, age sequence of Yema Lake section was established, and lake evolution and climatic change in the Shiyang River Drainage were reconstructed The result showed that dust storm events had occurred with 400a quasiperiod during Early Holocene(10 000-6 700 a B P ), the wettest climate phase The dust storm events occurred in the Shiyang River Drainage during Early Holocene were natural phenomenon relating with regional environment of Northwestern China