沉积磁组构在长江三角洲晚第四纪古土壤研究中的应用

APPLICATIONS OF MAGNETIC FABRICS TO THE STUDIES FO LATE QUATERNARY PALEOSOLS IN THE CHANGJIANG REVER DELTA AREA

本文研究了长江三角洲地区晚第四纪古土壤的沉积磁组构，其磁化率各向异性度Ｐ值较低，一般在１．０２０左右；磁线理Ｌ值和磁面理Ｆ值，也较低，均＜１．０２０；基质颗粒度ｑ值主要分布在＜０．５和＞０．７两个范围之内，代表正常沉积之中夹杂着相当量的事件沉积。由此得出结论，长江三角洲地区晚第四纪古土壤层的母质是河流冲积物。

This paper deals with the characteristics of the Late Quaternary paleosols in the Changjiang River Delta area. The paleosols here have a P value about 1.020 which repre- sents low energy,a L value between 1.004 and 1.020,and a F value between 1.003 and 1.020,which are different from those of the loess paleosol sequences on the Loess Plateau of China,The most of the q values are less than 0.5 or greater than 0.7,indicat- ing quite a few abnormal sediments among normal sediments.The author concluded that the parent material of the Late Quaternary paleosols in the Changjiang River Delta area was alluvium,of which those with a q value greater than 0.7 might be formed during flood.