Geochemical study of the redistribution of elements in soil—I. Evaluation of degree of weathering of transported soil materials by distribution of major elements among the particle size fractions and soil extract

摘要: Abstract Sixteen alluvial and terrace soils from Japan Thailand were separated into six fractions ; an amorphous sesquioxide combined organic matter fraction, crystalline sesquioxides, clay, silt, fine sand coarse sand. Content of ten major minor elements in these was analyzed; SiO 2 , A1 O 3 Fe MgO, CaO, K O, TiO Rb SrO determined by X-ray fluorescence spectrometry, Na neutron activation analysis. The mineralogy estimated semi-quantitatively diffraction methods. We propose three indices geochemical maturity for the test their usefulness as measures degree weathering. Three concomitant factors are proposed to measure relative resistate, hydrolyzate oxidate nature soils.