Intertidal Sedimentary Structures and Their Formation Mechanisms in Sandy, Muddy, and Sand-Mud Layered Flats

摘要

In the present study, we explored the capability of a surface wave method, called here MASW (Multi-channel Analysis of Surface Waves) in evaluating the cross-shore and along shore sedimentary structures of intertidal flats. Field surveys were carried out at sandy, muddy, and sand-mud layered flats, when these flats were exposed during spring tides in summer. The present method has proved very useful to investigate the sedimentary structures of various types of intertidal flats. The formation processes of the intertidal sedimentary structures can be explained as a consequence of cyclic elastoplastic contraction of soils that are subjected to a variety of suction dynamics under the tide-induced ground water table fluctuations.