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Scour and fill patterns in pool-rapid riversSilverston, Elliot, January 1975 (has links) (PDF)
Thesis (M.S. - Civil Engineering and Engineering Mechanics)--University of Arizona. / Includes bibliographical references.
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Scour and fill in a gravel-bed channel : observations and stochastic modelsHaschenburger, Judith Kay 05 1900 (has links)
This study investigates channel bed scour and fill as a result of individual flood events in a
gravel-bed channel. Given the complexity of interactions between hydraulic force, the texture and
arrangement of bed material, and input of sediment to a particular point of the channel bed, study
objectives were pursued with the view that bed material movement is a stochastic phenomenon.
A two-year field program was conducted in Carnation Creek, a small gravel-bed stream
draining 11 km2 on the west coast of Vancouver Island, British Columbia. In the 900 m study
reach, an array of measurement techniques, including scour indicators, magnetically-tagged stones,
and conventional survey, yielded information about the fluctuations of the channel bed elevation
and movement of scoured material for individual flooding periods.
Frequency distributions of scour and fill depths associated with individual flooding periods
are adequately modeled by negative exponential functions over the range of flood peak magnitudes
observed in Carnation Creek. Analysis of scour depths measured in streams on the Queen
Charlotte Islands demonstrates the applicability of the exponential model to flooding periods and
flood seasons. Further, exploratory analysis suggests that a regional scour depth model is
possible.
Power functions relating mean depths of scour and fill to flood peak discharge show that
depth increases with an increase in peak magnitude. Observed maximum scour depths in flooding
periods are linked, in general, to streambed conditions influenced by antecedent flow conditions.
These patterns in scour and fill exist within an overall pattern of increasing variability in depths of
scour and fill as peak discharge increases.
Evaluation of a heuristic model for mean travel distance as a function of particle size
proposed by Church and Hassan (1992) provides convincing evidence for its general merit. Mean
travel distance decreases inversely with particle size as size increases beyond the median diameter
of subsurface sediment. This trend is consistent in both individual flooding periods as well as
flood seasons. The majority of material finer than the median diameter of surface sediment is
supplied from subsurface material, which influences the travel distances of these finer fractions
because of burial. Computation of volumetric transport rates of bed material, based on the active scour depth
and width of the channel bed, the virtual velocity of particle movement, and sediment porosity,
suggests the potential for building scale correlations with streamflow, which have usually been
defined by bedload sampling during floods. Error analysis indicates that determination of active
width contributes most significantly to the imprecision of transport rate estimates.
Results underscore the stochastic nature of sediment transport in gravel-bed channels.
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Spatial And Temporal Trends In Sediment Dynamics And Potential Aerobic Microbial Metabolism, Upper San Pedro River, Southeastern ArizonaHamblen, Jennifer M. January 2003 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references (leaves 241-246).
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Scour and fill in a gravel-bed channel : observations and stochastic modelsHaschenburger, Judith Kay 05 1900 (has links)
This study investigates channel bed scour and fill as a result of individual flood events in a
gravel-bed channel. Given the complexity of interactions between hydraulic force, the texture and
arrangement of bed material, and input of sediment to a particular point of the channel bed, study
objectives were pursued with the view that bed material movement is a stochastic phenomenon.
A two-year field program was conducted in Carnation Creek, a small gravel-bed stream
draining 11 km2 on the west coast of Vancouver Island, British Columbia. In the 900 m study
reach, an array of measurement techniques, including scour indicators, magnetically-tagged stones,
and conventional survey, yielded information about the fluctuations of the channel bed elevation
and movement of scoured material for individual flooding periods.
Frequency distributions of scour and fill depths associated with individual flooding periods
are adequately modeled by negative exponential functions over the range of flood peak magnitudes
observed in Carnation Creek. Analysis of scour depths measured in streams on the Queen
Charlotte Islands demonstrates the applicability of the exponential model to flooding periods and
flood seasons. Further, exploratory analysis suggests that a regional scour depth model is
possible.
Power functions relating mean depths of scour and fill to flood peak discharge show that
depth increases with an increase in peak magnitude. Observed maximum scour depths in flooding
periods are linked, in general, to streambed conditions influenced by antecedent flow conditions.
These patterns in scour and fill exist within an overall pattern of increasing variability in depths of
scour and fill as peak discharge increases.
Evaluation of a heuristic model for mean travel distance as a function of particle size
proposed by Church and Hassan (1992) provides convincing evidence for its general merit. Mean
travel distance decreases inversely with particle size as size increases beyond the median diameter
of subsurface sediment. This trend is consistent in both individual flooding periods as well as
flood seasons. The majority of material finer than the median diameter of surface sediment is
supplied from subsurface material, which influences the travel distances of these finer fractions
because of burial. Computation of volumetric transport rates of bed material, based on the active scour depth
and width of the channel bed, the virtual velocity of particle movement, and sediment porosity,
suggests the potential for building scale correlations with streamflow, which have usually been
defined by bedload sampling during floods. Error analysis indicates that determination of active
width contributes most significantly to the imprecision of transport rate estimates.
Results underscore the stochastic nature of sediment transport in gravel-bed channels. / Arts, Faculty of / Geography, Department of / Graduate
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An operation study of the wheelwash dredge Sandwick /Higgins, Bruce J. January 1976 (has links)
Thesis (M.S.)--Oregon State University, 1977. / Typescript (photocopy). Date thesis presented: June 3, 1976. Includes bibliographical references. Also available on the World Wide Web.
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Temporal variability of riverbed hydraulic conductivity along the Great Miami River, southwest Ohio a continuance of data gathering and instrumentation /Windeler, Britton. January 2006 (has links)
Thesis (M. En.)--Miami University, Institute of Environmental Sciences, 2006. / Title from first page of PDF document. Includes bibliographical references (p. 32-35).
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Roadway effects on the hydrologic regime of temporary wetlands in the Missouri River floodplain in MissouriHorton, Kimberly. January 2005 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 11, 2007) Includes bibliographical references.
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Iceberg scour risk analysis for pipelines on the Labrador Shelf /King, Anthony D., January 2002 (has links)
Thesis (M.Eng.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 204-212.
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Application of stream classification and historical land uses for managed riparian systems of Eastern OregonZweygardt, Louanne R. 30 May 1995 (has links)
Twelve stream segments in the Silvies River drainage system were classified in
the fall of 1993 and again in 1994, using a morphological classification of natural
rivers (Rosgen 1994). Bankfull flow of stream channels is the key feature of this
system. Measurement of bankfull is used in the calculation of entrenchment ratio
and width/depth ratio. Analysis of the differences of the averages between years in
bankfull measurements showed that despite being consistently repeated at the same
locations along the channel, the measurements were found to be different
(p=0.000163 for entrenchment ratios and p = 0.0208 for width/depth ratios). Bankfull
was found to be a non-repeatable field measure, therefore, a poor benchmark for a
classification scheme.
Historical information collected for the study area indicated a history of domestic
livestock use that dates back as far as the mid-nineteenth century. Although grazed
by livestock for several years, settlement of the Bear and Silvies Valleys occurred
mostly around the turn of the twentieth century after the stockgrower's homestead
acts were passed. Ownership today is dominated by large (relative to the homestead
days) ranches. / Graduation date: 1996
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