Occurrence of fine chlorite (< 0.2 mu m) and its significance in the soilsfrom the Ulsan area, Korea

Well crystallized chlorite has been detected in a Typic Hapludult developed on quartz porphyry at Ulsan, Korea, after treatment of the <0.2 mu m fract ion with a high-gradient magnetic separation (HGMS) technique. The X-ray di ffraction (XRD) characteristics of the chlorite suggest that it is an Fe-ri ch variety and this was confirmed by energy dispersive spectroscopy (EDS) a nalysis. The chlorite could not be detected with certainty in the <2 mu m f raction but is clearly present throughout the soil profile in the <0.2 mu m fraction. It is suggested that this chlorite is residual inherited chlorit e, the rest of which has dissolved in the acidic environment (pH 4-5).