| The dissertation is sponsored by the project of National Nature Science Foundation Project Heterogeneity caused by the biological activity on the subaqueous Delta of Yellow River, and its aim is to study the dynamic response of sediment to the wave and the formation of the microsequence. About the formation of the microsequence, a lot of scholars have put forward their own view, but they have not united these views at present. But mainly origin cause of formation to study the microsequence comes in term of growing and depositting originally, but neglects the modification of the wave and trend to the sediment. The dynamic response of the sediment to the wave is related nearly to the seabed's geology environment and the gestation of the geology disaster. In this dissertation, the specificity of delamination is analyzed on the base of field and indoor test and the electrical resistivity test. First of all, the formal field survey data is generalized and we find out that the generally exist on the beach of Yellow River Delta. we took the undisturbed columniation sample of 0.5 meter on the beach and the microstructure has been observed with SEM and the transformation characteristics of the granularity have been contrasted continuously; While going on a large number of on-the-spot test jobs, the sediment's evolve is studied through the physical simulation in laboratory. At last, the electrical resistivity was combined in order to open out the mechanism of the microsequences.According to the analysis of the study results, a series of conclusion can be educed:(1)Field survey results indicate that hydrodynamics have an effective rebuild influence on the character of sediment, small granular surge up for the sake of hydrodynamics; The average grain of the sullage of the surface layer is among the small grain of the front mention and the matter due to biology active; thickness of sullage is related nearly to the strength of the mud; At the same time, the layer phenomenon has a distinctive character with a later formation character. (2)The on-the-spot test showed that, after the periodic load the soil turned on polarization in the depth of about 30 and 70 centimeters. Here the effective and the average diameter of the grains were smaller, and the change in other places was contrary to these two places.(3) Laboratory physics simulation test prove the phenomenon of small granular in the seabed transportation and the formation of layer during the concretion of sediment formed fleetly and cumulated. The existence of the crack has offered the channels for forming of bedding and drained off water but the content of particulate material of position that the migration of the particulate material makes the influent big in speed reduces, average one becomes great directly , even coefficient is reduced, grade of the soil is worthy of becoming bad; The layers of particulate materials in location of and the influent with little tempo are gathered , the average grain size of the soil is reduced, even coefficient increases, and grade of the soil is worthy of becoming well.(4) The electricity monitoring result has announced the characteristics of the sediment of the Yellow River estuary, and the migration route of the particulate material, thus explained the microsequence forming from mechanism. In this dissertation, some new points are got. For example, the space anisotropy of soil in seabed including minuteness layer, are caused either by original sediment process or by later alternation, or both of them. The component and microstructure of sediment along depth will change under cyclic load, with mostly variation concentrated above the extremum zone of excess pore water pressure. The stratified changes mainly happen in the initial stage of vibration, corresponding to pore water pressure's rising stage. The electricity monitoring result has reflected that a relatively stable soil layer exists in the powder soil layer in vibration mechanism; The form of the was based on the migration of the particulate material.
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