全新世浙江的海岸变迁与海面变化

本文就指示浙江古岸线与古海面位置的主要标志作了评述;首次公布了8个~(14)C测年数据,并据此及其他有关资料再现了浙江全新世海面变化;最后着重讨论了全新世海岸线变迁,提出四个不同的发展阶段。

Zhejiang's Holocene Coastline Shift and Sea Level Change

The changes of the Holocene sea level and the history of the Holocene coastline shift in Zhejiang are discussed, chiefly based on the ancient coastline evidences related with the sea level changes and 21 14C datings of shell, peat or mud and on wood samples along the Zhejiang coast. In the Early Holocene, sea level rose rapidly from -50m to -10m and there were two ancient coastlines which lay hidden under the submarine deposit varying in depth. In the early age of the Middle Holocene, sea level rose to the greatest height around 6,000-5,500 Y.B.P. and the Holocene transgression reached the greatest limits, thus forming an ancient coastline which was much more curved than today's coastline of Zhejiang. In the late age of the Middle Holocene around 5,000 Y.B.P., sea level tended to be stable and the coastline transformed the transgression into the regression owing to the deposit of sediment. Since the Late Holocene the development of Zhejiang's coastline has been divided into two stages. In the early stage, i.e. 2,500-1,000 Y.B.P. the coastline was comparatively stable and even made a little retreat. In the later stage, i.e. from 1,000 Y.B.P.to particularly the past 30 odd. Y, the progradation of the coastline has speeded up extensively because of the man-made factors, such as building seawalls and enclosing tideland and embankment for cultivation.