LINKING COARSE SILT PRODUCTION IN ASIAN SAND DESERTS AND QUATERNARY ACCRETION OF THE CHINESE LOESS PLATEAU
We suggest that whereas the fine-silt material in the CLP may be associated with variable sources, located even thousands of kilometers away, the coarse silt, a major component of the loess sequence, is derived by aeolian abrasion of the upwind proximal large sandy deserts, Mu Us, Tengger and Badain Jaran. Only these abraded coarse quartz grains can build up the mass of the loess sequence to form a massive and spatially well-defined loess plateau while the fine grain dust can be derived from everywhere. The more distal sandy deserts of Taklimakan, Qaidam, and Junggar cannot be major sources for the systematically deposited coarse silts and thinning trend (hundreds of meters in the north to several meters in the south) of the CLP. Long term persistent aeolian activity through time that both produce coarse silt quartz through abrasion of the immense Mu Us, Tengger and Badain Jaran dunes and delivers these abrasion products downwind, is a major process in forming the CLP.