【摘要】 <正> 我国大陆海岸线长约18,000公里,沿岸淤泥质潮滩分布很广。江苏的淤泥质潮滩是我国规模最大的潮滩之一。为了提供开敞海岸潮汐沉积作用模式,我们选择江苏省大丰县王港地区进行了比较详细的研究。 王港地区淤泥质潮滩的宽度在10公里以上,向海淤进速度较快,一般为50米/年。江苏岸外有巨大的海底沙脊群。沙脊群对受其屏蔽的潮滩的水动力有着重要影响。但王港地区与海底沙脊之间为一向北开敞的海域,其最窄处也宽达20公里,而且开敞的方向与本区的常风更多还原

【Abstract】 Along the 18,000 km coast line of China’s mainland,tidal mud flat is widely distributed.The tidal mud flat in Jiangsu Province is perhaps the longest and widest one in China.This paper deals with a prograding tidal mud flat along the open coast in the Wanggang area,Jiangsu Province.The recorded profile of Wanggang flat is 11.5 km long.Along the profile,a 25 hr.survey of the whole tide hydrographe and silts was carried out.Besides,usual laboratory analysis of sediments is made,and lacquer peels were taken.Sediments of the tidal mud flat are largely of silt size,which is closelyrelated to the source of sediments.Most sediments come directly or indir-ectly from the abandoned Huanghe River.The grain size is finest in sup-ratidal and upper intertidal zones,whereas the lower intertidal zone,subjected to wave and stronger tidal currents,is composed of coarser sediments,with some herringbone cross bedding.In the intertidal flat,thinly and coarsely inte’rlayered beddings are well developed.Their genesis is closely related to spring-neap cycle and annual cycle of variation of monthly mean sea level.The lack of flaser bedding in this region is probably due to the fact that its environment of deposition is considerably different from the North Sea Coast of Europe.No.14 typhoon of 1981 brought about widespread scour on the surface of the intertidal flat and deposition of coarse sediments with near horizontal bedding and cross bedding on the scoured surface.Finally,a model of vertical sequences of mud flat of meso-tidal open coast is proposed,a significant feature of which is the presence of many layers of storm deposits.更多还原