Constraining accretion rates in a tide-dominated, freshwater river (Pitt River, Canada) and implications for lateral accretion of channels in the tidal-fluvial transition

Date created: 
2015-08-20
Identifier: 
etd9217
Keywords: 
Vibracore
Tide-dominated
Mixed tidal-fluvial
Lateral migration
Bank accretion
Bend curvature
Abstract: 

A vibracore-based investigation of channel and floodplain deposits in the Pitt River Valley (PRV) was conducted to spatially and temporally confine the evolution of the PRV floodplain and the tide-dominated Pitt River. Sedimentological and ichnological assessment of cores is supplemented by geochronological and palynological analyses. The lateral migration rate of a Pitt River meander is quantified using Carbon-14 age dates of organic detritus at the base of a channel-margin core and the position of the core relative to the present-day channel profile. The Pitt River meander bar is shown to laterally migrate between 0.16 and 0.28 metres per year. A comparison of this rate to previous studies reveals that channels modulated by tides are capable of migrating at a rate equivalent to slowly meandering purely fluvial systems, and tidally affected channels migrate at less than 1.5% of the channel’s width each year.

Document type: 
Thesis
Rights: 
This thesis may be printed or downloaded for non-commercial research and scholarly purposes. Copyright remains with the author.
Supervisor(s): 
Shahin Dashtgard
Department: 
Science: Department of Earth Sciences
Thesis type: 
(Thesis) M.Sc.
Statistics: