Changes in channel morphology in response to two flood events were measured within three reaches on the Sainte Marguerite River, Quebec. The first event was the spring freshet---peaking in mid-May, 1996---while the second event---peaking on July 20, 1996---was the largest flood on record for the region. The resultant channel adjustments can be classified as either bedform evolution---in which a clear, systematic pattern of adjustment is evident---or as bedform change, in which local hydraulic and sedimen tologic conditions produce a seemingly random pattern of channel mobilization. Where bedform evolution has occurred, it is consistent with the existing paradigm for meander development. Sediment transport calculations based on the 'inverse' or 'morphologic' method were strongly correlated to reach average mobility ratios. The average rate of transport in response to the larger flood approached those reported by others for a braided system (Goff and Ashmore, 1994). Potential spawning zones within the three reaches were all subjected to significant net scour and/or fill following the second event; several potential spawning zones were significantly affected by the first event The presence of bank protection upstream of a potential spawning zone seems to be a determinant 10 the severity of the impact by promoting erosion of these zones.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.21545 |
| Date | January 1998 |
| Creators | Eaton, Brett. |
| Contributors | Lapointe, M. F. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Geography.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001658493, proquestno: MQ50760, Theses scanned by UMI/ProQuest. |
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