How does water shape the land (rivers and coasts, erosion, weathering, ox bow lakes etc)?

Question

How does water shape the land (rivers and coasts, erosion, weathering, ox bow lakes etc)?

Answer 1

It's all to do with the relationship between erosion and deposition.

So take a coastline for example, the sea can erode away cliffs and cause the coastline to retreat.  You can also get erosional landforms such as sea arches and sea stacks.  On the other hand you get depositional landforms such as beaches and spits.  So the sea is eroding the rocks and sediments in one area, and depositing it in other areas as sand or mud or shingle.

In rivers, the rivers can erode down the rock over which they flow creating canyons.  Meanders in rivers are caused by the flow on the outside of the bend which is flowing faster eroding the river bank.  On the inside of the bend the flow is slower meaning that sediment is deposited.  This means the meanders move creating oxbow lakes.

Water also causes erosion, especially by something called freeze thaw weathering.

Water also shapes the landscape whilst as ice.  Going back to the last glacial maximum the northern UK, Wales and Scotland were covered by ice sheets and glaciers.  These gouged out valleys, cirques/cwms/corries (all the same thing!), mountain ridges etc (arretes).  You can see these in the UK.

Ice also created depositional landforms, such as eskers (snaking ridges of sediment).

There's loads more info on the web and in books that you can have a look at to see examples and find out more about coastal, river and glacial erosional and depositional landforms and landscapes.

I think this is a fascinating side of geography, enjoy!

Answer 2

the water hits the land and the atoms fall off and get washed away

Answer 3

What is erosion?                        

~the process by which water, ice, wind or gravity moves weathered rock & soil

What is important about moving water?

~it is the major agent of erosion that shaped Earth’s land surface

What is runoff?        

~water that flows over the ground surface rather than soaking into the ground

~picks up soil particles as it moves

How does the amount of runoff affect erosion?          

~in general- more runoff means more erosion

~few plants = high erosion

What are rills?

~tiny grooves in the soil made by flowing  water

What is a gully?                        

~as rills flow into one another they erode a large channel in the soil called a gully

How is a stream formed?

~gullies join together and form a channel of water continually flowing down a slope

~large streams are called rivers

What is a tributary?                    

~a stream or river that flows into a larger river

What is a watershed/ drainage basin?    

~the area from which a river and its tributaries collect their water

Why do rivers often form a deep, V-shaped valley?    

~near its source, fast flowing water erodes steep slopes

How do waterfalls form?        

~water passes over rock that is not easily eroded

~then over an area of soft rock which wears away quickly forming a drop

What is a flood plain?          

~land on either side of a river that gets flooded during wet seasons

What does it mean for a river to meander?                                

~river forms a channel that bends from side to side

What causes river meanders?    

~easily eroded rock on the outer bank erodes

~sediment is deposited on the inner bank

~forms a curve or a loop

What is an oxbow lake and how does it form?            

~a meander that’s been cut off from a river

~river floods & finds a straighter route downstream

~flood ends, & sediments dam up ends of meander

What does water drop when it slows down?        

~sediment- rocks / fine particles

What is an alluvial fan?                

~wide, sloping deposit of sediment formed where a stream leaves a mountain range

What is a delta?                        

~sediment build-up where a river flows into an ocean or lake

~usually arc- or triangle-shaped

How does soil get on flood plains?    

~when flood water retreats it deposits sediment as new, very fertile soil

What are beaches?                      

~areas where sand carried downstream by the river spreads along the coast

What is groundwater?                

~water that soaks into the ground

~it affects the shape of the land

How does groundwater shape the land?      

~causes erosion through chemical weathering—carbon dioxide and water form carbonic acid

~breaks down limestone

~hollows pockets in rock

~over time forms caves and caverns

Answer 4

Water erodes in the river using many different techniques. In a typical river, the outside bend gets eroded more because the current is faster. So the inside bends gets deposited on, because the current is slower. As the river meanders, the neck of the meander gets narrower and narrower due to erosion and depostion until eventually, the river comes out of the meander and an oxbow lake is formed.

The term weathering is the the break down of rock in situ without the removal by the process in which broke it down.

Including freezethaw, when water seeps into a crack or joint in a rock, and then during cold temperature, the water freezes roughly to 9-10% and then when the temperatures rise again, the water starts to melt (thaws) and this process repeats, until an angular fragment breaks off called scree.

Corrie Lakes are formed during glaciation, when a North Facing hollow in the ground gets filled with snow, which then compresses to form ice. The ice then erodes the hollow to make it deeper. The process used are Plucking and Abrasion. The water then melts to leave a corrie lake.

A Ribbon lake is formed on the floor of a glacial trough or U shaped valley, where there is less resistant rock which has been pulled out when the glacier was moving. This hole then fills with water.

Headlands and bays are formed when beds of harder rock and softer rock on the coast get eroded. The main process of erosion is Hydraulic Action and that is the force of the water dislodging material in the cliff side, and the softer rocket gets eroded more due to it being less resisitant and this forms a bay. The Harder more resistant layers gets eroded less, leaving headlands.

I hope this helps :) If you need anymore help email me :)

Edit: And to the last answer about "atoms" that is the biggest load of rubbish I have ever heard! xD

Answer 5

Mostly, because water erodes away land. But also, with salt water, the salt in the surrounding air changes the coast.

For example, the water from the Colorado River sculpted the Grand Canyon.

If you are asking how do lakes have the shapes they do, that's just because the water runs off to the lowest point, that would have nothing to do with the water, just the geography.

One more thing, land can be eroded/changed from water because water can seep into cracks, freeze, and expand the crack. When it gets severe, it shapes the land.

Hope that helped....