【摘要】 本文回顾和总结了不同纬度带大河三角洲全新世相对海平面曲线的特征及影响因素。以相近纬度带的长江、尼罗河与密西西比河三角洲为例,剖析了全新世中期无“高于现代平均海平面”的“壅水”现象,认为直布罗陀海峡、加勒比海岛屿和白令海峡对北极圈南下融水进入地中海、墨西哥湾和西太平洋起到了限制作用。大量的研究还表明,距今约7ka时尼罗河三角洲相对海平面低于现今约14m,而此时密西西比河三角洲相对海平面约为-10m,长江三角洲仅约为-5m;随后,它们的差距逐渐减小,反映了沉降作用对相对海平面变化的影响。论文提出一种利用全新世三角洲沉积层序、结合相对海平面曲线来判断区域沉降差异的方法;总结了三角洲古地形对海平面上升的响应模式,以及利用三角洲新石器遗址“最低居住面”重塑全新世相对海平面变化的路径。这些均为三角洲地区全新世海平面变化与地貌环境演化的相关研究提供了新的前景。更多还原

【Abstract】 This paper summarizes the distribution and driving force of the Holocene sea levels of various mega-deltas at different geographic locations.Using the Changjiang River,the Nile River and the Mississippi River deltas as an example,this paper discussed the low impact of global hydro-isostacy on regional sea-level rise during the midHolocene.This can be explained by the unique landforms where these deltas are located,which is able to restrict a large volume of melted water from the Antarctic flowing into the regional seas.Also,the paper stressed the role of subsidence.For example,the relative sea level(RSL) position of the Nile River,the Mississippi River and the Changjiang River lays at ca.-14 m,-10 m,and-5m at ca.7ka B.P.,respectively,and then approaches to the present while narrowing their gaps.This indicates the role of regional subsidence,which inevitably affects the RSL positions.The paper also proposes a simple method for assessing the subsidence rate,a relationship of sea level rise to paleo-topographic gradient and the ’ lowest habitable base’ of the Neolithic settlement,which helps reconstruct the Holocene sea level.All these shed lights on the perspective of the Holocene sea level rise in relation to delta evolution in future study.更多还原