中文摘要：

利用钱塘江南岸萧山地区SE2孔的粒度资料,分析了粒度参数、频率分布曲线和概率累积曲线的特征,并结合沉积物的岩性、沉积构造和有孔虫的分布特点,探讨了该区自晚第四纪以来的沉积环境演化。结果表明,晚第四纪以来,钱塘江南岸地区依次接受了河床相、河漫滩相、潮坪相、近岸浅海相和河口湾相5种沉积。河床相沉积物以砂砾为主,粒度参数变化较大,概率分布曲线为3段式,频率分布曲线为不对称的双峰式,主要发育块状层理,生物化石稀少。河漫滩相以细砂、粉砂级沉积物为主,频率分布曲线为单峰式,富含生物壳体碎屑和植物根茎。潮坪相沉积物表现为粉砂和黏土互层沉积,粒度参数变化频繁,频率分布曲线多为双峰式,韵律层理发育。近岸浅海相沉积物主要为淤泥质黏土,粒度参数稳定,概率分布曲线为2段式,以悬浮组分为主,频率分布曲线为单峰式,有孔虫含量丰富。河口湾相沉积物以粉砂和细砂组成的韵律性沉积为主,粒度参数富于变化,概率分布曲线为3段式,频率分布曲线为双峰式。

英文摘要：

Data of grain-size,lithology,sedimentary structures and paleontology of the Core SE2 in southern bank of the Qiangtang River,are used to interpret the environmental evolution in this area.The study suggests that there are five types of deposits in Core SE2 from bottom to top：Fluvial channel,floodplain,tidal flat,shallow marine,and estuary.Fluvial channel sediments which consist of sandy gravel have a wide range of grain-size parameters distribution,showing three parts in probability accumulation curves and two humps in grain-size distribution curves.The floodplain sediments,of which the grain-size distribution curves show single hump,mainly compose of silt and fine sand at intervals and have abundant bioclasts and phytoclasts.Compared with floodplain deposits,tidal flat sediments have wider range of grain-size parameters and consist of rhythmic couplets constructed by silt and clay.Shallow marine sediments,mainly composed of muddy clay,have stable grain-size parameter distribution,and show two parts in probability accumulation curves and single hump in most of their grain-size distribution curves.A large number of foraminifers were found in this sedimentary facies.Estuary sediments,mainly made up by silt and fine sand,have variable grain-size parameters,and consist of three parts in probability accumulation curves and two humps in grain-size distribution curves.