| The hydro-geomorphological system and the development of the rocky tidal inlet bays in China are discussed mainly by a classic case study of Jiaozhou Bay.Based on the acquired studies, the geomorphology of the rocky bays in China are studied statistically and classified. A throat jet coefficient (Rbjet) is worked out to divide the tidal inlet bay from others based on the hydrodynamic mechanism and the movement of the tide in a bay. The coefficient mentioned above is applied and checked in the rocky bays of China, and a tidal flat - tidal channel or a tidal flat - tidal channel - tidal ridge geomorphology system is developed when Rbjet is larger than 45, which means that the bay is a tidal inlet bay, and a tidal flat geomorphology system is developed when Rbjet is smaller than 45.Jiaozhou Bay is selected as the classic case to study the hydro-geomorphology and development of the rocky tidal inlet bays in China. Other than studied it inside or outside partially as before, we regard the tidal basin (inside), the throat and the ebb tidal delta (outside) as a whole tidal inlet system linked by the throat jet. A large quantity of data is collected including the cores, sub-bottom, sea-beam, the depth, the sediment (mainly the type, granularity and the heavy minerals), the current and suspended sediment from the recent new projects as well as the data mentioned before. The optimum data is selected out according to the spatio-temporal distribution to analyze the geomorphology and development both inside and outside of the bay, and much attention is paid to the interrelation and integrity of the inside and outside part of the bay. And the main contents are:I. Based on the relief, sediment distribution and the tidal current (Da integrate tidal inlet hydro-geomorphological system including the flood tidal delta (inside), the throat and the ebb tidal delta (outside ) is formed; (2) the characteristics of the form and the develop conditions of the two type bottom figures - sand waves and tidal ridges are discussed;II. the transport trend of the bottom sediment and suspended sediment is studied according the distribution of granularity and heavy minerals, and the deposition-erosion trend of the tidal inlet of Jiaozhou Bay is worked out by contrast of the depth along the profiles between different years of 1935, 1962-1966 and 1992;III. to study the formation mechanism and period of time of the tidal inlet of Jiaozhou Bay.Based on the studies it is found that a classic tidal inlet geomorphology system is developed in Jiaozhou Bay. The geomorphological units formed bidirectional but asymmetry, and they are not all consistent with the dominant tidal current, which means that the tidal inlet geomorphology is somewhat successive. According to the cores and sub-bottom, the tidal inlet geomorphology system formed between 9. 000 a B.P. when seawater entering the bay and 5,700a B.P., which is the time just after the MaximumTransgression. During the mentioned period of time, the strong tidal current scoured the tidal inlet out and the other geomorphological units formed. Currently, the sediment supply is limit in Jiaozhou Bay, the sediment exchanges a little inside and outside of the bay, and the net transportation trend of the bottom sediment and suspended sediment both direct inside. The contrast of the water depth along the profiles show that the erosion and deposition mainly occurred in and near the tidal channels, and the whole trend inside the bay is deposition, while it is erosion outside, which is inconsistent with the net transportation trend of the sediment, and further more it is inconsistent with the hydrodynamic trend that flood tidal current dominates in the bay.
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