Grain size distribution of quartz isolated from Chinese loess/paleosol

Grain size distribution of bulk loess-paleosol and quartz chemically extrac ted from the loess/paleosol shows that mean size of the bulk samples is alw ays finer than that of the quartz, The original aeolian depositions have be en modified to various degrees by post-depositional weathering and pedogeni c processes. The grain size distribution of the isolated quartz should be c lose to that of the primary aeolian sediment because the chemical pretreatm ent excludes secondary produced minerals. Therefore, the grain size of the quartz may be considered to more clearly reflect the variations of winter m onsoon intensity.