- Potholes. Potholes are cylindrical holes drilled into the bed of a river that vary in depth & diameter from a few centimetres to several metres.
- V-Shaped Valleys. V-Shaped valleys are found in the upper course of the river and are a result of both erosion by the river and weathering.
- Waterfalls (Geological) Waterfalls develop when a change of lithology (rock type) takes place along the river’s course resulting in differential erosion.
- Rapids. Rapids are sections of a river where the gradient of the river bed is relatively steep resulting in an increase in the river’s turbulence and velocity.
- Meanders. Meanders are bends in a river that form as a river’s sinuosity increases. ...
- Oxbow Lakes. Oxbow lakes are an evolution of meanders that undergo extensive deposition and erosion. ...
- Braided Channels. A braided channel is a type of channel that is divided into smaller sub-channels by small, temporary islands called eyots.
- Floodplains. Floodplains are large, flat expanses of land that form on either side of a river. ...
- Levees. Levees are natural embankments produced, ironically, when a river floods. ...
- Deltas. Deltas are depositional landforms found at the mouth of a river where the river meets a body of water with a lower velocity than the river (e.g. ...
What is a pothole?
Potholes are round/oval shaped holes in the bedrock of a river bed. Potholes on the River Ure, close to Ayesgarth Falls. They are formed when sediment and other material carried by a river scour the bed. Where depressions exist in the channel floor turbulent flow can cause pebbles to spin around and erode hollows through abrasion/corraision .
How are potholes formed by erosion?
Potholes - cylindrical or hemispherical holes formed by erosion in bedrock rivers - are one of the principal ways in which rivers erode landscapes. Once initiated as small depressions on rock surfaces, potholes can deepen and widen owing to abrasion by sediment.
How did the potholes in the Appalachian Mountains form?
The sediment being moved by the glacier, along with the structure of the underlying bedrock, together created the potential for potholes. As glaciers retreated, and melting waters turned to phenomenal rivers, the sediment that they carried along with them did the work of carving out the hole in the creek bed.
Why do Potholes form in crib dams?
Potholes. The intention of this crib dam may have been to regulate water flow and redirect water to a trench for use elsewhere. As you can see, the crib dam continues to sufficiently regulate water flow. But when water levels are high, the excess water begins to spill over the edges and create new pathways.
How do potholes form in a riverbed?
A pothole is a circular or cylindrical hole in the riverbed which is produced by force of water and abrasion. A pothole is formed when a circular current of water carrying small pebbles and sediment begins to wear away a rock surface.
How do potholes form in water?
Potholes are created when groundwater seeps into the ground underneath the pavement. If the water freezes, it will expand, thus causing the pavement to expand, bend and crack. When the ice melts, gaps or voids are left in the surface under the pavement.
What are potholes formed by?
Potholes are holes in the roadway that vary in size and shape. They are caused by the expansion and contraction of ground water after the water has entered into the ground under the pavement. When water freezes, it expands. Think of when ice cubes are made.
Are potholes caused by erosion?
When a rock layer is exposed to running water under a stream or river, potholes can form by the action of water currents and turbulence. The movement of water, pebbles and sand can cause erosion to form potholes and depressions in the rock.
What pothole means?
1a : a circular hole formed in the rocky bed of a river by the grinding action of stones or gravel whirled round by the water. b : a sizable rounded often water-filled depression in land. 2 : a pot-shaped hole in a road surface. 3 : a usually minor difficulty or setback hit a pothole in her comeback attempt.
What are the effect of potholes?
Some of the more common damage is a flat tire or damage to your tires, bent or damaged rims, suspension damage, steering damage and even damage to the body of the car. Potholes can even knock your car out of alignment so it will affect the way the tires wear and can lead to replacing tires before earlier than expected.
How do potholes affect the environment?
Potholes are aggravating to drive over, and they can cause billions of dollars of damage every year to automobile wheels, tires and suspensions. Currently, road crews fill in these holes with hydrocarbon-containing asphalt, but that material can leach out, polluting the environment.
How can we prevent potholes?
Preventing and Repairing PotholesSealing. Crack sealing and slurry sealing keep water from penetrating the surface by sealing small cracks. ... Overlays. Overlays are a more intensive treatment in which a layer of compacted asphalt is constructed to seal the surface and add some structural strength. ... Reconstruction. ... Patching.
Why do potholes happen when it rains?
After lengthy periods of rain, like what we've been experiencing, some road pavements become saturated. The water in the pavement is compressed under the weight of traffic and this compressed water pops out any weak point in the asphalt forming a pothole.
What kind of physical erosion is a pothole?
“Mechanical weathering is the breakdown of rocks into sediments through physical means. For example, weathering can carve out potholes in our streets, break down rocks to form soils, and even tear down mountains.” The major types of mechanical weathering processes are as follows: Frost wedging.
Are potholes natural?
Throughout Natural Bridges, naturally occurring sandstone basins called “potholes” collect rain water and wind-blown sediment, forming tiny ecosystems where a fascinating collection of plants and animals have adapted to life in the desert.
Why do potholes form in winter?
Water under road freezes and expands Sometimes, when it rains, that water can seep below the asphalt. When freezing temperatures hit the water, under the road's surface expands and stuff shifts around. And then when it melts, pressure from something, such as a car, can cave in the payment and create a pothole.
What type of weathering causes potholes?
“Mechanical weathering is the breakdown of rocks into sediments through physical means. For example, weathering can carve out potholes in our streets, break down rocks to form soils, and even tear down mountains.”
Why do roads get holes after rain?
HOW IS A POTHOLE FORMED IN ASPHALT? 3. When the weather warms up, the ice pockets melt and the water drains through the road base. This not only leaves voids under the roads surfaces but it can also soften the road base.
How do potholes form in warm climates?
These cracks can appear due to heavy traffic or extreme heat. Water can easily drain into these cracks and wash out the layers of stone or dirt that support the pavement. Eventually, an air gap is created within the sub-base of the asphalt pavement.
Does ice cause potholes?
Water under road freezes and expands Sometimes, when it rains, that water can seep below the asphalt. When freezing temperatures hit the water, under the road's surface expands and stuff shifts around. And then when it melts, pressure from something, such as a car, can cave in the payment and create a pothole.
The Science
Potholes - cylindrical or hemispherical holes formed by erosion in bedrock rivers - are one of the principal ways in which rivers erode landscapes. Once initiated as small depressions on rock surfaces, potholes can deepen and widen owing to abrasion by sediment.
The Poet
Hywel Griffiths is a Senior Lecturer in Physical Geography in the Department of Geography and Earth Sciences, Aberystwyth University, Wales. He is a fluvial geomorphologist and poet, writing mainly in the Welsh strict meter form of cynghanedd, based on alliteration and internal rhyme, elements of which can be seen in this poem.
What is a river pothole?
A river pothole is a cylindrical, bowl-shaped, or
How thick is a pothole?
each of which are up to 20 feet thick. A pothole or series
How wide is a pothole in basalt?
Pothole about one foot wide in the basalt
Where does the Niobrara River feature occur?
features occurs on the channel floor of the Niobrara River
Is a channel smooth sloping?
channels are not smoothly sloping or of uniform depth,
Where do potholes occur?
Undoubtedly potholes frequently happen in the beds of streams and waterways. However, they are not limited to the courses of present-day streams, as they additionally happen on the beach, on slope tops, and steeply inclining rocks where it is hard to envision any previous stream. Alexander noted (Alexander, p. 308):
What is a pothole?
In common understanding, potholes are viewed as the impacts of erosion by streams and waterways over significant periods. The genuine work of scraped spot is considered to have been done either by hard grains of sand held in suspension by the quickly streaming water; or by huge stones, called “processors,” in the base of the pothole, that were fomented continually by the current twirling around inside. The modest grains in the fast flows are thought to have step by step worn out the stone into a downturn, the movement of the processors developed that.
Why are there potholes in the mountains?
Potholes that happen a long way from streams and valleys, at times high up on slopes and mountains, are clarified by geologists as the impacts of the incredible ice periods of the Quaternary. Apparently, during this time, there were potholes shaped when the ice liquefied, as waterways streamed underneath the ice and on its surface. In some cases, these surface waterways plunged down a chasm, and disintegrated the bedrock underneath, framing potholes on the most remote spots, the glacier scholars’ guarantee.
What is the rock on the slopes between Red Horse and American waterways?
On the slopes between Red Horse and American waterways, the diggers have washed away the overlying rock. The stone underneath the rock is specially smoothed and cleaned, yet is lopsided, containing many adjusted despondencies bowls, and potholes up to 5 feet inside and out.
What would happen if the ocean had been beating the shores where the bedrock was secured with a slight layer?
For if the ocean had been beating the shores where the bedrock was secured with a slight layer of rock, the sand would be washed away soon and the highlights underneath uncovered, including potholes. The water would not have cut them, yet only uncovered them. What is more, the equivalent applies to streams.
How deep is Taylor Falls?
Alexander noted one case of 12 feet in breadth and 60 feet deep at Taylor Falls. (Alexander, p. 305). Customary topography experiences no difficulty pleasing such prolonged period ranges; however, a creationist translation requires this sort of impact in only two or three thousand years, in the time passed since the Biblical flood. (Morris, 1974).
Do potholes belong to ages in development?
The gradualness of the procedure of scraped area by which the potholes should have been shaped appears to demonstrate the holes would belong ages in development. However, this issue is additionally intensified by the way that by far, most of all, potholes are not during the time spent arrangement right now.
What is a pothole in JavaScript?
Potholes. Potholes are cylindrical holes drilled into the bed of a river that vary in depth & diameter from a few centimetres to several metres.
Why are V-shaped valleys found in the upper course of a river?
They’re found in the upper course because this is where the river has the greatest gravitational potential energy and so the greatest potential to erode vertically. It does so during periods of high discharge. When the river’s discharge is high, it is able to transport its large bedload by traction eroding the river’s bed and valley by corrasion, deepening it. Not much lateral erosion takes place so the channel and valley remains relatively narrow.
What is a bend in a river that form as a river’s sinuosity increases?
Meanders. Meanders are bends in a river that form as a river’s sinuosity increases. The sinuosity of a river is a measurement of how much a river varies from a straight line. It’s a ratio between the channel length and displacement (straight line distance) between two points in the river’s course:
How does a river's load work?
In the upper course of a river, its load is large and mainly transported by traction along the river bed. When flowing water encounters bedload, it is forced over it and downcuts behind the bedload in swirling eddie currents. These currents erode the river’s bed and create small depressions in it.
Why are the sides of a valley steep?
If the valley is composed of hard rock the valley sides will be very steep because they won’t be weathered easily. Waterfalls (Geological) Waterfalls develop when a change of lithology (rock type) takes place along the river’s course resulting in differential erosion.
What is the term for a section of a river where the gradient of the river bed is relatively steep?
Rapids. Rapids are sections of a river where the gradient of the river bed is relatively steep resulting in an increase in the river’s turbulence and velocity. They form where the gradient of the river is steep and the bed is composed mainly of hard rocks. Meanders.
Why do the sides of the valley take up a V shape?
As the channel and valley deepens the sides of the valley are exposed and become susceptible to weathering. The valley’s sides also undergo mass movements resulting in large volumes of material falling into the river’s channel, adding to its erosive power and causing the valley sides to take up a V shape.
How are potholes formed?
A pothole is formed when a circular current of water carrying small pebbles and sediment begins to wear away a rock surface.
Why are there potholes in Hungarian Falls?
Geologists associate potholes with large volumes of very turbulent water. Most often they are thought to be associated with the melt water of a glacier. This is likely the case here at Hungarian Falls, as we can point to additional evidence to demonstrate that glacial activity in this area was prominent in the last 1-2 million years. As glaciers advanced, they scoured out the softer sediment, essentially wiping this area clean of any loose rock, and carrying it along. The sediment being moved by the glacier, along with the structure of the underlying bedrock, together created the potential for potholes. As glaciers retreated, and melting waters turned to phenomenal rivers, the sediment that they carried along with them did the work of carving out the hole in the creek bed.
What is a crib dam?
A crib dam is a man made structure of interlocking timbers (much like a log home) which is laid across a creek bed and filled with stones . The intention of this crib dam may have been to regulate water flow and redirect water to a trench for use elsewhere.
