中文摘要：

通过对江苏中部淤泥质潮滩潮汐纹层发育过程的实地观测，以及对所采样品在室内进行的落淤量的计算与颗粒的粒度、磨圆度分析等，揭示出江苏中部海岸淤泥质潮滩沉积中的潮汐层理的成因机理：毫米级薄砂泥互层层理为半日潮的产物，厘米级厚的厚砂泥互层层理为半月天文潮的产物。此外，通过对9711号台风引致的风暴潮影响前后的滩面进行了现场观测，发现江苏中部淤泥质潮滩上部存在一个即使在风暴潮期间也不发生侵蚀的地带。该带的风暴沉积与正常的潮滩沉积比较，具有粒度较粗，分选较差，磨圆稍好，递变现象明显，平行层理或波状交错层理发育比较典型的特征。

英文摘要：

Field observation on the formation and development process of silt-mud couplets is carried out on tidal flat of the middle Jiangsu province. Combined the observation result with the calculation of sedimentation quantity and the analysis of grain-size and roundness of sedimentary particles, the mechanism of silt-mud couplets is revealed in this area. One thin silt-mud couplet with the thickness of millimeters is formed during a flood-ebb tidal cycle, and one thick couplet with the thickness of centimeters is formed during a spring-neap tidal cycle. In addition to the research on the formation of silt-mud couplets, the field observation on the tidal flat is carried out before and after the storm surge for typhoon No. 9711. The result shows that even during storm surge period, high tidal flat can still be in sedimentation over some places, no erosion occurred. Compared with the normal tidal flat sedimentation, the storm sedimentation has the characteristics of coarse particle, bad sorting, relatively high roundness, obviously graded bedding, typical parallel bedding, cross bedding.