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| Titel |
Bar morphodynamics in the tidally-influenced fluvial zone |
| VerfasserIn |
Daniel Parsons, Philip Ashworth, James Best, Andrew Nicholas, Eric Prokocki, Greg Sambrook-Smith, Claire Keevil, Steve Sandbach |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250112056
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| Publikation (Nr.) |
 EGU/EGU2015-12213.pdf |
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| Zusammenfassung |
| The hydrodynamics and deposits of the Tidally-Influenced Fluvial Zone (TIFZ) are complex because it experiences competing fluvial and tidal flows and spatially and temporally variable rates of sediment transport and deposition. This paper presents a new integrated field dataset from the Columbia River Estuary, USA, that quantifies the morphodynamic response the bed morphology and bar stratigraphy to fluvial-tidal flows.
A 3-year, field and modelling program that started in 2011, has been monitoring the dynamics and deposits of a 40 km-reach of the Columbia River Estuary. Data obtained so far throughout the TIFZ include: bathymetry using MBES, flow using ADCP, subsurface sedimentology using GPR and shallow coring to 5 m.
Initial results from the programme suggest there is a complex spatial and temporal lag in the response of the bed morphology and deposits to the fluvial-tidal flows. Zones of strong ebb and flood flow do not necessarily produce channel beds dominated by bi-directional bedforms. Many mid-channel bars are stable over decadal time periods. This paper will illustrate the variety in bar morphologies and channel change throughout the fluvial-tidal zone and contrast these bar dynamics with examples from purely fluvial environments. |
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