Loess–paleosol stratigraphy of Dukso area, Namyangju City, Korea (South)

As Korea lies between China, with a drier climate, and the wetter Japanese Islands, the Korean loess–paleosol stratigraphy constitutes an important record of variations in the East Asian monsoon climate. The loess–paleosol sequence consists of three loess layers (L1LL1, L1LL2, and L2) and three paleosols (L1SS1, S1, and S2) in the study area. L1LL1 accumulated near the surface, and is only about 5 cm in outcrop because it was removed for farming. L1SS1 is about 103 cm thick. Soil crack structures developed in the upper part of L1SS1 were formed by shrinkage or as seasonally frozen ground soil wedges during the early cold-dry stage of glacial period. L2 is 48 cm thick, with OSL ages of 167,000 and 186,000 yr. Magnetic susceptibilities of paleosols were higher than the loess layers. Fine quartz grains in the loess layers are characterized by rounded shape and pitted surfaces. Based on the presence of the AT tephra, OSL ages, soil color, soil crack structure, magnetic susceptibility, and median diameter, the loess–paleosol sequence of the Dukso section can be correlated with the Chinese loess–paleosol sequence between MIS 2 and 7.