한반도 중남부 내륙 분지에 발달한 화강암 사질풍화층의 화학적 풍화 특색

Abstract

Granitic regoliths are characterized by non-red deep regoliths in basins and reddish regoliths in low-hills of Southern Korean Peninsula. But all granitic deep regoliths of Korean Peninsula have been regarded as saprolites which were weathered chemically. If deep regoliths are not formed by alterations, it is not saprolite but grus or arene. Non-red sandy regoliths are plotted under feldspar join on A-CN-K ternary diagram and under a feldspar-biotite line on A-CNK-FM ternary diagram. Reddish regoliths are plotted along A-K boundary one-sided to A peak(Al2O3) on A-CN-K ternary diagram and over feldspar-biotite line on A-CNK-FM ternary diagram. Because the weathering trends are parallel to the A-CN boundary, non-red sandy regoliths may have been transformed to reddish by the progression of alteration. Therefore, non-red sandy regoliths in the basins should be called grus and reddish regoliths saprolite, not laterite.