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Studies the folding of intertidal sediments on the West Lancashire Coast in England. Correlation between the formation of the folds by porewater and sediment movements and the growth of dune bedforms; Analysis of key issues of interest; Implications on sedimentology.

Describes a sequence of tide-dominated offshore sediments from the Lower Cambrian of north Norway. Interpretation of relative importance of possible processes in their transport and deposition; Lateral facies variations and sedimentary structures; Four facies defined in terms of grain size, bed thickness and sedimentary structures.

In Dutch sub-tidal waters, mud settling from suspension can produce a layer with a thickness of only some millimetres in one slack-water period. However, consolidated mud layers of 10–25 mm thickness in sub-tidal deposits are often observed. This indicates that mud may be preserved over several slack-water periods. This is only possible if the critical shear velocity (U∗c) for the initiation of sediment movement is not surpassed after slack water. Tube and flume experiments reveal: (1) Thicker mud layers have smaller initial consolidation rates and lower values of U∗c. (2) A higher sand content of the mud always gives a more rapid initial consolidation. The U∗c-values increase to a maximum which is reached at a sand content of 40%. Higher sand contents lead to decreasing values of U∗c. (3) For one particular mud sample the U∗c-values increase linearly with the mud concentration Of the bed material. (4) After three hours of consolidation a mud layer may carry a sharply bounded sand layer 0.5 cm thick. By application of the results of the experiments to natural conditions in tidal water some tentative explanations are possible of the formation of flaser, lenticular and sand-clay alternating bedding. [ABSTRACT FROM AUTHOR]

Describes a quantitative model of climbing ripples and their cross-laminated deposits. Equation of the angle of climb of ripples in cross-laminated deposits; Assumptions of gradually varied flow to predict the spatial patterns of cross-lamination types in deposits; Definitions of deposition and erosion.

Examines changes in size frequency distribution of sedimentary particles trapped at successive heights above an eroding surface. Variation of wind strength, initial surface size distribution and particle shape; Role of particle shape in rate of sediment movement; Derivation of equations for the change in sediment concentration with height.

Physiographic features and depositional history of the sediments forming the bed and banks of the lower 200 miles of the Mississippi River are summarized. From mile 200160 the river is scouring into coarse substratum sands, between miles 160 and 80 into Pleistocene clays, and between mile 80 and 0 chiefly into prodelta and interdistributary clays. Point-bar accretion averages 500 acres per river mile in the uppermost segment, 200 acres per river mile in the middle segment, and 30 acres per river mile in the lowermost segment. The occurrence of bends caused by faulting or formed during seaward growth of the delta, and the occasional existence of coarse materials in the path of the Stream are significant factors in the initiation of meanders. The composition of the bed and banks, and the length of channel occupation are important in the rate and extent of migration. Migration of the river between miles 0 and 160 has been and should continue to be very slow. [ABSTRACT FROM AUTHOR]

An anomalous increase of pore volume with increasing depth in the range 0-1,900 ft. Occurs in fine-grained sediments along the east side of the San Joaquin Valley of California. Several possible causes for the anomaly were inferred from a literature search and from study of the core samples. Statistical analyses of the core sample data suggest the principle causes to be variations in particle size, the diatom-skeleton content, and the type of exchangeable cation adsorbed by the clay-mineral constituents of the sediments. [ABSTRACT FROM AUTHOR]