|The Application of Radioisotopes in the Study of Estuarine Sedimentary Processes|
Clifton, R.J.; Hamilton, E.I. (1982). The Application of Radioisotopes in the Study of Estuarine Sedimentary Processes. Est., Coast. and Shelf Sci. 14(4): 433-446
In: Estuarine, Coastal and Shelf Science. Academic Press: London; New York. ISSN 0272-7714, more
Americium; Cesium; Distribution; Estuaries; Mixing; Polonium; Radionuclides; Ruthenium; Salt marshes; Sediment transport; Sedimentation; Spatial distribution; ANE, British Isles, England [Marine Regions]; British Isles, Scotland, North Esk R. [Marine Regions]; Marine; Brackish water
|Authors|| || Top |
- Clifton, R.J.
- Hamilton, E.I.
The use of radionuclide distributions and ratios as indicators of sedimentation and remixing processes within the Newbiggin area of the Esk estuary was investigated. It was demonstrated how, in conjunction with other physical and chemical characteristics of the sediments, these radionuclides may influence the ultimate fate of the non-conservative radioisotopes present in the region. The estuary is flanked by an emerging salt marsh and is a region exposed to a variety of radionuclides resulting from the activities of the British Nuclear Fuels Ltd. The dominant sediment of the area is a coarse grained sand resting on beds of indurated shingle. In the estuary, tidal movement of sediment results in the deposition of local areas of fine grained arenaceous silt on sands. The concentration of non-conservative radionuclides in surface sediments of the area cannot be described by a single parameter, but there is a high correlation of organic C, Cu, Al and the Si:Al ratio with particle size. The preservation of the historical record of the BNFL effluents in the Esk sediment is dependent on the hydrology of the area, which affects accretion, erosion, and remixing. Sedimentation rates at sites of accretion vary between 0.5 and 3 cm/year. However, at some sites they are much higher, about 6 cm/yr in the top 10 cm, but they are not consistent throughout the depth profiles. Some cores show evidence of continous accretion, but no significant radioactivity was detected at depths below 35-40 cm, indicating an overall sedimentation rate of about 1.5 cm/yr for the 25-30 yr period since BNFL effluents first entered the Irish Sea.