Point bar

point bar deposits
A point bar is a depositional feature made of alluvium that accumulates on the inside bend of streams and rivers below the slip-off slope.wikipedia
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Meander

meandersoxbowincised meander
Point bars are found in abundance in mature or meandering streams.
A meander is produced by a stream or river as it erodes the sediments comprising an outer, concave bank (cut bank) and deposits this and other sediment downstream on an inner, convex bank which is typically a point bar.

Slip-off slope

A point bar is a depositional feature made of alluvium that accumulates on the inside bend of streams and rivers below the slip-off slope.
The deposition of material at the toe of a slip-off slope often results in the formation of a point bar.

Cut bank

cutriver cliffthe flats
A point bar is an area of deposition whereas a cut bank is an area of erosion.
As opposed to a point bar, which is an area of deposition, a cut bank is an area of erosion.

Oxbow lake

oxbowoxbow lakesox-bow lake
An old fallacy exists regarding the formation of point bars and oxbow lakes which suggests they are formed by the deposition (dropping) of a watercourse's suspended load claiming the velocity and energy of the stream decreases toward the inside of a bend.
The process of deposition of silt, sand and gravel on the convex bank is clearly illustrated in point bars.

Secondary flow

secondary circulationSecondary flow in turbomachinerysecondary flows
Point bars are formed as the secondary flow of the stream sweeps and rolls sand, gravel and small stones laterally across the floor of the stream and up the shallow sloping floor of the point bar. (Tropical cyclones, tornadoes, and the spinning motion of water as it escapes down a drain are all visible examples of vortex flow.) In the case of water flowing around a bend in a stream the secondary flow in the boundary layer along the floor of the stream does not flow parallel to the banks of the stream but flows partly across the floor of the stream toward the inside of the stream (where the radius of curvature is smallest).
This process can lead to accentuation or creation of D-shaped islands, meanders through creation of cut banks and opposing point bars which in turn may result in an oxbow lake.

Bank erosion

erodeerosionlateral erosion
A point bar is an area of deposition whereas a cut bank is an area of erosion.

Alluvium

alluvialalluvial soilalluvial deposits
A point bar is a depositional feature made of alluvium that accumulates on the inside bend of streams and rivers below the slip-off slope.

Stream

creekstreamscreeks
A point bar is a depositional feature made of alluvium that accumulates on the inside bend of streams and rivers below the slip-off slope.

River

riverineriparianleft bank
A point bar is a depositional feature made of alluvium that accumulates on the inside bend of streams and rivers below the slip-off slope.

River island

fluvial islandislandislands
They are crescent-shaped and located on the inside of a stream bend, being very similar to, though often smaller than, towheads, or river islands.

Sorting (sediment)

sortingwell-sortedpoorly sorted
Point bars are composed of sediment that is well sorted and typically reflects the overall capacity of the stream.

Elevation

hightopographic elevationelevated
They also have a very gentle slope and an elevation very close to water level.

Flood

floodingfloodsflood control
Since they are low-lying, they are often overtaken by floods and can accumulate driftwood and other debris during times of high water levels.

Topography

topographicaltopographictopographer
Due to their near flat topography and the fact that the water speed is slow in the shallows of the point bar they are popular rest stops for boaters and rafters.

Flash flood

flash floodingflash floodsflash-flood
However, camping on a point bar can be dangerous as a flash flood that raises the stream level by as little as a few inches (centimetres) can overwhelm a campsite in moments.

Deposition (geology)

depositiondepositsdeposit
A point bar is an area of deposition whereas a cut bank is an area of erosion. An old fallacy exists regarding the formation of point bars and oxbow lakes which suggests they are formed by the deposition (dropping) of a watercourse's suspended load claiming the velocity and energy of the stream decreases toward the inside of a bend.

Vortex

vorticesvorticalvortex lines
Any fluid, including water in a stream, can only flow around a bend in vortex flow. Mass deposition of suspended solids rarely occurs on one bank save in tidal estuaries; instead, vortex flow being faster on the inner bank compensates for the greater height and therefore mass of water flowing downstream along the concave bank, and the rough, shallow bed usually provides per liter of water above more agitation to maintain any suspended particles.

Tropical cyclone

hurricanetropical stormhurricanes
(Tropical cyclones, tornadoes, and the spinning motion of water as it escapes down a drain are all visible examples of vortex flow.) In the case of water flowing around a bend in a stream the secondary flow in the boundary layer along the floor of the stream does not flow parallel to the banks of the stream but flows partly across the floor of the stream toward the inside of the stream (where the radius of curvature is smallest).

Tornado

tornadoestornadicwedge tornado
(Tropical cyclones, tornadoes, and the spinning motion of water as it escapes down a drain are all visible examples of vortex flow.) In the case of water flowing around a bend in a stream the secondary flow in the boundary layer along the floor of the stream does not flow parallel to the banks of the stream but flows partly across the floor of the stream toward the inside of the stream (where the radius of curvature is smallest).

Boundary layer

boundary layersboundary layer theoryboundary-layer
(Tropical cyclones, tornadoes, and the spinning motion of water as it escapes down a drain are all visible examples of vortex flow.) In the case of water flowing around a bend in a stream the secondary flow in the boundary layer along the floor of the stream does not flow parallel to the banks of the stream but flows partly across the floor of the stream toward the inside of the stream (where the radius of curvature is smallest).

Suspended load

suspended sedimentsuspendedsuspension
An old fallacy exists regarding the formation of point bars and oxbow lakes which suggests they are formed by the deposition (dropping) of a watercourse's suspended load claiming the velocity and energy of the stream decreases toward the inside of a bend.

Angular momentum

conservation of angular momentumangular momentamomentum
This fallacy relies on the erroneous notion that the momentum of the water is "always" slowest on the inside of the bend (where the radius is smallest) and fastest on the outside of the bend (where the radius is greatest), which ignores its increased angular momentum.

Tide

tidalhigh tidelow tide
Mass deposition of suspended solids rarely occurs on one bank save in tidal estuaries; instead, vortex flow being faster on the inner bank compensates for the greater height and therefore mass of water flowing downstream along the concave bank, and the rough, shallow bed usually provides per liter of water above more agitation to maintain any suspended particles.

Suspension (chemistry)

suspensionsuspensionsaqueous suspension
Mass deposition of suspended solids rarely occurs on one bank save in tidal estuaries; instead, vortex flow being faster on the inner bank compensates for the greater height and therefore mass of water flowing downstream along the concave bank, and the rough, shallow bed usually provides per liter of water above more agitation to maintain any suspended particles.

Coefficient

coefficientsleading coefficientfactor
Any relatively steady gradient open flow not met with complex interactions with contrary flows, such as tides, or major obstacles, flows around a bend in a simple model of vortex flow, with relatively few variables and coefficients.