| What can Erosion create? Where is it Found? | -They create Erosional Features; found in the Upper Course of the River |
| What is a Waterfall? | -This is a Sudden Drop along Course of the River.
-This happens because of Resistant Rock [Hard Rock] is above Less Resistant Rock [Soft Rock] that is Exposed. |
| Explain the Steps on how the Waterfall is Created | 1] Soft Rock is eroded Faster than the Hard Rock.
2] As this Erosion of the Soft rock Continues, the Hard Rock is Undercut, and Hangs over.
3] Abrasion and Hydraulic Action creates a Plunge Pool
4] The Plunge Pool gets bigger with time, which then Increases the Size of the Hard Rock Overhanging, until its own Weight can't be supported which results into an Collapsing
5] This keeps Happening again and again; the Waterfall Retreats Upstream
6] Where the Waterfall once was leaves Steep-Sided valley. This is a Gorge |
| How can Interlocking Spurs be Formed? | -The Upper Course of an River has more Vertical Erosion, which means it cuts Down into the Valley
-If it reaches Hard Rock which is very hard to Erode, the River will Bend around it
-This makes Interlocking Spurs that can link Together, like a Zip. |
| Why in the Middle Course can Meandering happen? | -It can happen because:
-There is more Water; Energy
-Lateral Erosion widens the River |
| What is Meanders? | This is Large Bends of the River, that happens due to Lateral Erosion |
| Why can Meandering happen? | -When the River goes around a Bend, the Majority of the Water is pushed into the Outside. This increases Speed, and Erosion rates [Hydraulic Action and Abrasion]
-The Outer Bend erodes, and Undercuts the bank to make a River Cliff
-So the Outside side Erodes.
-The Water on the Inner Bend is more Slower, which results into Deposition taking place. Gentle slope of Sand and Shingle is Present
-This build up of the Sediment can be named as a Slip-off Slope, or a River Beach
-So the Inside Deposits
-Those 2 sides Bend Left or Right.
-And also, the Fastest Current 'Bounces' meaning that it won't bend in 1 direction forever. |
| How can Oxbow lakes form? | -So since the Erosion of the Outer bend, and the Deposition on the Inside, the Meander shape will change over some Time
-Erosion will narrow the 'Neck' of the Land within the Meanders, and as time keeps ticking, the Meanders will be Closer Together
-When Huge Discharge has Happened [Flood] the River can simply Cut through the Neck
-This results in 2 things:
-The River now takes on a Straight and Shorter Route
-Deposition occurs, that Cuts of the Meander, which then has a Horse show Shaped Oxbow lake, that is not connected to the River |
| What is a Floodplain? | -This is simply Area of Land that is Covered in water. |
| How can Floodplains happen? | -This happens from Erosion and Deposition
-Erosion takes away the Interlocking Spurs, which results in Wide, Flat area being Established both sides of the River
-When a flood occurs, Material is Deposited, because the River loses its Speed and Energy to take the Material
-The Height of the Floodplain increases with time, because Deposition occurs on the Sides of the River. |
| Why are Floodplains sometimes Agricultural Land? | -Land there can be Very Fertile, as because of Alluvium being in the Soil
-Alluvium is Deposited Silt from a River Flood |
| What do Floodplains look like? | -They are most commonly Wide, Flat area that is caused because of Meanders shifting along the Valley |
| Where can Levees occur? | -They can occur in the Lowest Course of a River, when the Volume of Water flowing down Increases, and Flooding happens |
| How does Levees happen | -So the Sediment that has been Eroded upstream is taken down here via Transportation
-When the River floods, the Sediment is Split across the Floodplain
-When a Flood happens, the River Loses energy. Large Materials is Deposited first on the Sides of the River Banks, with Smaller Materials Further away
-After a number of floods, the Sediment builds to add on to the Height of the River Bank. Bigger height equals More Water Capacity, and flooding can be less Likely to happen |
| What is an Estuary? What happens to the River in a Estuary? Why is it Important? | -This is the Point where the River meets the Sea
-The River becomes Tidal, and so when the River Retreats, the Volume of Water goes down.
-Less water equals Deposits of Silt to create Mudflats, which is an Important Habitat for Wildlife |
