摘要
本文主要根据作者对国内外三角洲调查分析资料，论证了中国沿海大河三角洲的沉积旋回、基底构造、形成年代、沉积层序和沉积特点的可比性，但其形态类型、沉积相组合和发育程度颇有差别，体现了世界全新世各大三角洲发育的共同性与差异性。
For the past over 15 years, active investigation was carried out, mainly using coring and sonar profiling, to study the sedimentological/geomorphologic processes of the major late Quaternary deltas, such as Ruan River delta, Yellow River delta, Yangtze River delta, Han River delta and Pearl River delta, distributed along the eastern coast of China. It is found that there obviously exist many respects of similarity and discrepancy in delta formation, reflecting that the late Quaternary delta processes influenced by eustasy, isostasy and climatic fluctuation are extensively comparable, even though different backgrounds of physiographic zonations along the eastern coast of China played an important role in affecting the delta development. Similarity of late Quaternary delta processes includes l) the tectonic subsidence inducing delta depocenter shift in space and river channel migration, 2) late Pleistocene basal stiff muds, which reflect alluvial sedimentation during the lower stand of sea level, 3) Holocene transgressive sands which is progressively combined with the fluvial sediment landward, 4) mid to late Holocene delta sediment sequences, which are primarily composed of three sections, i. e. from bottom upward, the pro-delta, delta front and delta plain, 5) changes of coastal environmental facies which coincides with the vertical changes of the Holocene facies. and 6) Holocene delta initiation. which started from～7 000 aBP, tested by many radiocarbon isotopes. These respects can be believed as worldwide as the research on Nile and Mississippi deltas were recently finished. In addition to the above-mentioned similarities, it is evident that vital discrepancies exist in the delta construction, resulted from deferential physiographic backgrounds, for instance the sediment input and hydrodynamic features around delta estuary. These features can be regarded as the direct factors in causing the dissimilar configuration of delta geomorphology, such as the fluvio-dominated type, fluvial-tide-dominated type and wave-
出处
《地理学报》
CSSCI
CSCD
北大核心
1995年第6期481-490,共10页
Acta Geographica Sinica
基金
国家自然科学基金
关键词
三角洲
共同性
差异性
中国
河流
similarity, discrepancy,delta processes, eastern coast of China
