Fig. 3: Changes along the channel profile in Bute Inlet.
From: Rapidly-migrating and internally-generated knickpoints can control submarine channel evolution
Location is shown in Fig. 2a. KPZ = knickpoint-zone a Bathymetric profiles along the channel thalweg in 2008 and October 2016. 50x vertical exaggeration. The position of the channel shifts as the channel evolves, so profiles were constructed along the position of the thalweg in that survey. Profiles were then normalised to allow comparison. Slope was generated using the survey from October 2016. Note the downstream alternation of deposition (blue) and erosion (red). Three main erosional areas (knickpoint-zones) are bounded at their upstream end by steep steps (frontal-knickpoint) in the channel profile. Additional smaller knickpoints are often present within wider knickpoint-zones. Proximal erosion upstream of knickpoint-zone 1 is due to lateral migration of the channel, unrelated to knickpoint migration. b Difference in channel elevations between March 2008 and October 2016 along the channel thalweg. Migration of three knickpoint zones (KPZ 1 to 3) produces erosional areas.
