上海及长江口第四纪沉积层中埋盖的古河道

在第四纪时期,上海及长江口由于地质构造、古气候、海面升降等综合作用,第四纪沉积层中与之相适应的埋盖了七期古河道。文中指出埋盖古河道的形成与发育是因袭了基底深切沟谷的走向。古河道的摆动、延缩、埋盖,是受古气候冷热交替制约。文中还指出研究埋盖古河道的演变规律,不仅对上海及长江口变化、海陆变迁有着指导意义,而且对城市供水及长江口外大陆架供水有着重大经济意义。

THE BURIED CHANNELS IN THE QUATERNARY SEDIMENT AT THE MOUTH OF THE YANGTSE RIVER AND IN SHANGHAI AREA

During the Quaternary Period, there buried seven-stages of paleochannels, corresponding to the tectonic movement, the alteration of paleoclimate and the fluctuation of the sea level. The paper illustrates that the strikes of the deep-cut basement river valleys controlled the formation and development of the buried channels, and that the alternation of th paleo- climate governed the migration, the extending and shortening as well as the burial of the river valleys. Besides, the paper pointes out that the study of the the evolution of the paleo- channels is not only of theortical importance but also of economic significance for the supply of water for the cities in this area and the continental shelf beyond the mouth of the Yangtse River.