Climatic implications of loess deposits from the Beijing region

Variations in magnetostratigraphy, pedostratigraphy, grain size and magnetic susceptibility of the loess deposits near Beijing have been studied at two sections. The sections are about 400 km east of the main loess deposits in China, have a maximum thickness of 100 m and extend back to 1.1 Ma. The sequence consists of 14 loess-palaeosol couplets (SO-S14), which correlate well with sequences in the Loess Plateau. Susceptibility records from the sites near Beijing are comparable to the Xifeng, Luochuan and Baoji sections located in the middle part of the Loess Plateau; however, the down-core variations in the grain size in the Upper Lishi Formation exhibit some differences. The median grain size increases by about 25-30 mum from L4 to L2, with the sandy grains (> 63 mum) increasing from 10-20 wt% to 40-50 wt%. This implies that the depositional environment of the dust sources in the Beijing loess section is different in some aspects from the Loess Plateau. The Beijing loess may have had a different dust source than the Loess Plateau. Copyright (C) 2001 John Wiley & Sons, Ltd.