Sedimentology and channel slope morphology of an anoxic basin in Southern Netherlands
Faas, R.W.; Wartel, S. (1976). Sedimentology and channel slope morphology of an anoxic basin in Southern Netherlands, in: Wiley, M. (Ed.) Estuarine Processes: Volume II. Circulation, sediments, and transfer of material in the estuary. pp. 136-149 In: Wiley, M. (Ed.) (1976). Estuarine processes: II. Circulation, sediments, and transfer of material in the estuary. Academic Press: New York. ISBN 0-12-751802-X. xv, 428 pp., more |
| Abstract | The Veerse Meer is a brackish, non-tidal lake in southern Netherlands. It was separated from the tidal Oosterschelde in 1961 by dams at each end. Environmental and sedimentological changes are occurring that are different from the parent water body. Bottom conditions range from well-oxidized to completely anoxic. Physical properties of the bottom sediments vary, depending upon the bottom water conditions. Bioturbation in aerobic areas has mixed the pre- and post-1961 sediments. Areas which became anoxic shortly after enclosure show a lack of mixing, with post-1961 clayey sediments lying directly over pre-1961 sandy sediments. Extensive levelling of the pre-1961 bottom is occurring with fine-grained sediments accumulating in scour pits and depressions. Channel slope measurements show three distinct morphologies, each reflecting changes in the dynamic history of the estuary. "Cliffed" slopes are relict features from the pre-1961 tidal system. "Steep" slopes are found adjacent to channel sides in anoxic environments and contain fine-grained sediments. "Gentle" slopes found adjacent to mid-channel sand islands are composed of coarser-grained sediments. Nature of post-1961 sedimentation appears directly influenced by 1) biologic activity, 2) wind wave and boat wake winnowing, 3) proximity to polder drainage channels and tidal flats, and 4) lack of tidal activity. |
|
