福建沿海晚更新世以来的海平面变化

Sea level changes since Late Pleistocene along Fujian coast

本文选择了六类79个具有14C年龄和准确高程的古海面标志物，按北、中、南三个岸段分别建立了三条相对海平面变化曲线，讨论了福建沿海晚更新世以来的海平面变化特征和规律。通过比较也分析了不同岸段的新构造差异升降情况。

On the Fujian coast, a variety of the Late Quaternary sea level indicators have been recognised. We have established in this paper three relative sea level curves along the northern,middle and southern sections of the Fujian coast based on 79 selected radiocarbon dates from 6 types of sea level indicators such as beachrock,oyster reef and in situ oyster shell,chenier ridge, saltmarsh peat, macrobotanical remnant, and marine-terrestrial transitional strata with fossil organisms. The curves show that the Late Quaternary sea level changes in the three coastal sections all followed the fluctuation patterns,and there was no great differences in time for the occurrence of the high and low sea level stands among the different coastal sections. For the whole Fujian coast,it appears that the relative high sea levels during the Late Pleistocene took place at about 42ka, 37k^34ka,B. P. and 25k^22ka,B. P-. During the Early Holocene,sea level had been rising with a fluctuation pattern. By about 8k^7ka,B.P. sea level had reached its present position, and then attained its highest stand at about 5. 6ka,B. P.. Since then,sea level has been fluctuating between 3m and -2m. During the periods of 6. 7k^5. 6k, 3. 6k^2. 9k, 2. 4k^1. 8k, 1. 6k~ 1. 2ka,B. P.,sea level had attained the elevations higher than the present mean sea level. The sea levels lower than the present position occurred during the periods of 5. 5k ~ 5k, 4. 2k ~ 3. 9ka, B. P. and 2. 8k ~ 2. 5ka, B. P.. By comparison of the relative sea level stands it can be seen that the northern coastal section has subsided relatively to the middle and southern coastal sections since the Late Pleistocene.During the Early Holocene,Meizhou Island along the middle coastal section had uplifted relatively to the continent with a certain degree. Since 6ka,B. P.,sea level trends have been quite similar,suggesting that the three coastal sections have been tectonically relatively stable during this period.