Magnetic properties of typical paleosol and loess stratum of western loess plateau and its signification to paleocliamte

The magnetic properties of the Heilu soil unit and upper Malan loess unit of JZT profile located in the west of the loess plateau were compared.The relationship between magnetic properties and pedogenesis was discussed.The results show that the loess depositing after the late pleistocene had the properties that its content is low;the magnetite is the dominating magnetic mineral and maghemite,hematite and goethite contents could be detected;the magnetic mineral domain is intermediate between SD and MD.The magnetic properties are significantly different:Heilu paleosol contains more magnetite,haematite and/or maghaemite and less goethite in concentration,the magnetic domain is more close to the single-domain;Malan loess has more goethite and less ferromagnetic minerals,the magnetic domain is more close to the multi-domain;the transition's magnetic properties are between the above-mentioned two soil units and close to Malan loess.