Search results
Results from the WOW.Com Content Network
Erosion and changes in the form of river banks may be measured by inserting metal rods into the bank and marking the position of the bank surface along the rods at different times. [23] Thermal erosion is the result of melting and weakening permafrost due to moving water. [24] It can occur both along rivers and at the coast.
Whether formed by chance or necessity, by headward erosion or downslope convergence, whether inherited or newly formed. [1] Depending on different geological factors such as weathering, erosion, depositional environment, and sediment type, different types of channel patterns can form.
In the cycle of erosion model, knickpoints advance one cycle upstream, or inland, replacing an older cycle. [1] A knickpoint that occurs at the head (furthest upstream extent) of a channel is called a headcut. [2] Headcuts resulting in headward erosion are hallmarks of unstable expanding drainage features such as actively eroding gullies. [3]
A downslope view of part of the eroding rill network from County Tyrone, Northern Ireland.See below for a close-up view of a single rill. In hillslope geomorphology, a rill is a shallow channel (no more than a few inches/centimeters deep) cut into soil by the erosive action of flowing surface water.
Stable material on the river bed mitigate erosion, [10] removing this armoring layer of gravel, boulders, etc. exposes the channel bed to the erosive force of the water. "On the Russian River near Healdsburg, California, instream pit mining in the 1950s and 1960s caused channel incision in excess of 3-6 m over an 11-km length of river." [5]
As erosion of the knickpoint and the streambed continues, the head cut will migrate upstream. [3] Groundwater seeps and springs are sometimes found along the face, sides, or base of a head cut. [4] [5] Channel incision is very common when head cuts are involved in stream morphology. In terms of stream restoration, head cuts are one of the most ...
Headward erosion is erosion at the origin of a stream channel, which causes the origin to move back away from the direction of the stream flow, lengthening the stream channel. [1] It can also refer to the widening of a canyon by erosion along its very top edge, when sheets of water first enter the canyon from a more roughly planar surface above ...
The channel head is the most upslope part of a channel network and is defined by flowing water between defined identifiable banks. [1] A channel head forms as overland flow and/or subsurface flow accumulate to a point where shear stress can overcome erosion resistance of the ground surface. [1]