珠江三角洲地区新构造运动年代学的研究

CHRONOLOGICAL STUDY ON NEOTECTONIC MOVEMENT IN ZHUJIANG DELTA AREA

本文发表珠江三角洲地区14个不同时代的地貌体的年代数据,并据此初步探讨三角洲地区晚第四纪以来新构造运动的时间、空间序列以及运动的幅度和速率。

Fourteen age data published in this paper were obtained from various geomorphic elements in the Zhujiang delta area, which were formed in various geologic times. The authors discuss the neotectonic movement in this area since Late Quaternary based on these data and consider that from the late stage of middle Pleistocene to the early stage of Epipleistocene, the crust in the area was comparatively stable, while a vertical movement started in the, late stage of Epipleistocene. The uplift amplitude of northern block reaches about 14-15m with a rate of 0.4-0.7mm/a, and the subsidence amplitude reaches about 16-20m with a rate of 0.5-0.7mm/a. The subsidence amplitude of southern block reaches 22-50m with a rate of 0.7-1.8mm/a. Since the Holocene the uplifted area tends to be stable or slightly downcast, and the subsidence area still continues to subside at a rete of 0.9-4mm/a. The subsidence amplitude increases gradually from northern to southern part of the area.