River sediments deposition patterns

Mitra, S., Dickhut, R.M., Kuehl, S.A., and Kimbrough, K.L. (1999b) Polycyclic aromatic hydrocarbon (PAH) source, sediments deposition patterns, and particle geochemistry as factors influencing PAH distribution coefficients in sediments of the Elizabeth River, VA, USA. Mar. Chem. 66, 113-127. 

Q. D. E. Walling, 1996. Use of fallout Pb-210 measurements to investigate longer-term rates and patterns of overbank sediment deposition on the floodplains of lowland rivers. Earth Surf. Process. Landforms 21 141-154. 

Rivers continually erode the geosphere over which they flow and leave deposits of sediments. Over time, a river will erode earth away and create valleys. An undisturbed river continually cuts curving patterns known as meanders in a river valley. The flat area of a valley formed by erosion and sediment deposition in the vaUey and susceptible to periodic flooding is the river s floodplain. 

DCB, and 2,6-DCB] as the river flowed over contaminated upstream sediments. Thus, they hypothesized that the composition of the PCBs available for deposition in the downstream sediments had already undergone major changes. This theory led to the conclusion that the alterations in PCB residue patterns found in bottom sediments were not likely to be the result of in situ weathering processes. Instead they were seen as caused by the scavenging from the water column of previously altered mixtures of PCBs by suspended particles or water-filtering macrophytes growing in the sediments. 

Mai, B.X., Zeng, E.Y., Luo, X.J., Yang, Q.S., Zhang, G., Li, X.D., Sheng, G.Y., Fu, J.M., 2005b. Abundances, depositional fluxes, and homologue patterns of polychlorinated biphenyls in dated sediment cores from the Pearl River Delta, China. Environ. Sci. Technol. 39, 49-56. 

The deposition of marine mud in the Sound is part of a regional pattern of onshore transport of fine-grained suspended sediment over the Atlantic shelf (Meade, 1969 Hathaway, 1972). The accumulation of marine muds in the Sound has been investigated by Bokuniewicz et al. (1976). The Sound was established as an arm of the sea about 8000 yr BP and, when this happened, fine-grained sediment particles from the shelf waters and the rivers of New England began to be transported into the Sound and incorporated in deposits of marine mud. The floor of the central and western Sound is the top of a layer of mud many meters thick. 

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