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Rare earth element (REE) compositions of the suspended sediments from the rivers around the Yellow Sea were different in that Korean river sediments (Han, Keum and Yeongsan Rivers) yield stronger fractionations than Chinese river sediments (Changjiang, Huanghe and Yalujiang), shown by obvious enrichments of LREE (light rare earth element) relative to UCC (upper continental crust). Variations of source rock compositions in the drainage basins are responsible for the differences of REE compositions between the river sediments. REE fractionation parameters including (La/Yb)UCC and (Gd/Yb)UCC as well as the ratios of La/Sc and Th/Sc can be treated as proper proxies for identifying the Chinese river sediments from those Korean river matters, and furthermore, for studying the provenances and paleoenvironmental changes of the marginal seas of China.

The late Quaternary paleosols in the Yangtze Delta area developed in the period of 25 000–12 000 aBP. Phytolith ratios (value A) of contents of fan, square and rectangle types indicating the warm and humid climate to those of bar, hat and point types indicating cold and dry climates decrease upwards overall on profiles of the paleosols, suggesting that the climates turned from warm and humid to cold and dry. So, the paleosols developed mainly during the regression before the last glacial maximum. Changes of value A indicate no trend of warming, suggesting that the transgression was rapid after the last glacial maximum. The development of the paleosols exhibited obvious stages, which were controlled remarkably by transgression and regression: I. Period of alternation of deposition and pedogenesis, which was from the occurrence of regresson before the last glacial maximum to the time when sea levels fell close to the lowest; II. Exposure period with continual pedogenesis, which was terminated when the paleosols were drown in the post-glacial transgression; III. Period of being drown and buried, the paleosols were buried by marine sediments, and reworked by early diagenesis.

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values ofP, F andL of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

The result of measurements and analyses on magnetic fabrics data for the late Quaternary core at Caoyangxincun in Shanghai shows that abrupt changes of magnetic fabric curves coincide with the boundaries between the marine strata and underlying stiff clay. Littoral, neritic, subtidal and tidal flat facies in the marine strata have distinct magnetic fabric characteristics. The curves of the parameters,K, P, L, q, display clear boundaries between various facies, which could serve as a new method for the stratigraphic subdivision and correlation.

The volumes of each sedimentary facies in the Qiantongjiang estuary area have been calculated based on layer thickness data of about 100 bores. The sediment sources of each facies have been discussed on the basis of the previous work and the above calculations.

IN the southern Yellow Sea there exists a large radial sand ridge system,which covers about 20 000 km2. Sand ridges and troughs occur alternately within the system, and single sandridges are tens of kilometers, even more than one hundred kilometers long and ten to fifteenkilometers wide. Due to the distribution pattern of the radial sand ridge system being like finer...