摘要
本文对中国、日本晚更新世古沙丘(中国称为'老红砂')的分布、高度、规(?)粒度、化学性质、沉积结构、地层层序及其成因等进行了全面对比分析。作者认为,(?)丘的沉积层序表明,最终冰期至少有四次环境变化的旋回;古沙丘的颜色特征则表明其红土化作用与亚间冰期的温暖古气候有关。
Paleodunes formed during the late Pleistocene are called the Old red sand in China. They are distributed extensively along the coast of Japan Sea in Japan and along the coast of South China. The dune areas are divided into two types, the calcareous sand and the non—calcareoussand, of which the latter is more common. A paleodune in Japan generally contains four paleosoils which divide the dune sand into four parts. The four major periods of dune formation are as follows: 20 000 a B.P. , 30 000 a B. P., 50 000 a B.P. and 70 000 a B. P.. But only the former three periods have been found in China. According to the distribution, elevation and scale, grain size, chemical characters, depositional structure and stratigraphic sequence, it is recognized that the origin of paleodune or Old red sand is mainly eolian. The paleodunes developed mainly as a result of cold and dry climate during the last glacial age. The depositional sequence of paleodunes and paleosoils shows at least four cycles of environment change and every cycle consists of subglacial - low sea level - paleodune and subinterglacial - high sea levelpaleosoil during the last glacial age. The Old red sand in China is characterized by its red or orange color, while the paleodunes in some areas of Japan has red or brownish red weathering layer with a thickness of 1-2m. It seems that there was a certain relationship between the red soil action and the warm paleoclimate during the sub interglacial.
出处
《热带地理》
北大核心
1993年第1期1-12,共12页
Tropical Geography
关键词
中国
日本
沙丘
晚更新世
China
Japan
Paleodune
Old red sand
