Bulk magnetic susceptibility was measured using a Kappabridge (KLY-4 or MFK1, AGICO). Anisotropy of magnetic susceptibility (AMS) was measured using the manufacture's SUFAR software program, and bulk susceptibility was calculated from the AMS tensor. Chemical digestion by citrate-bicarbonate-dithionite, and sodium pyrosulfate fusion to extract eolian feldspar and quartz. XRD analysis was conducted using a diffractometer (MiniFlex II, Rigaku) with Cu Ka radiation. The samples were first dispersed in a 0.2 % sodium hexametaphosphate solution and sonicated for 1h. The dispersed sample was then introduced into a laser diffraction particle size analyzer (Mastersizer 3000E, Malvern Panalytical).