Magnetic susceptibility, anhysteretic susceptibility, frequency-dependent and temperature-dependent magnetic
susceptibilities
are measured before and after citrate-bicarbonate -dithionite (CBD) treatment on the Holocene loess-black loam sequence from Jiaodao, Shaanxi province. In this paper, we employ the correlativity between anhysteretic and magnetic
susceptibilities to determine the domain state of magnetic minerals of the studied profile. The differences between pre- and post--CBD susceptibilities imply that not only the ultrafine superparamagnetic, but also some larger single-domain grains can be produced due to pedogenesis. Thermomagnetic analyses of the typical Holocene loess and black-loam specimens and
magnetic susceptibility measurements before and after CBD treatment show that CBD has no absolute selectivity of dissolving the pedogenic magnetite grains, although it can efficiently dissolve the pedogenic maghemite grains. The results also show that CBD technique strongly supports the pedogenic model of susceptibility enhancement. In addition, a combination study of soil chemistry and rock magnetism supplies a new evidence for the eolian origin of Chinese loess.