Geography - Rivers Flashcards
What is a river?
- fresh flowing water
- bottom of river = riverbed
- sides of the channel = river bank
Which is the longest river in the world?
River Nile
Where and which continent are these river found in: Amazon River, River Severn, River Nile
Amazon River: Brazil, South America
River Severn: England, Europe
River Nile: Egypt, Africa
Longest river in Europe?
- Volga river
- Valdai hills
- Russia
- Northwest of Moscow to east / southeast
- Empties in the Caspian sea
- 2300 miles / 3700km
Longest River in the UK?
- River Severn
- 220 miles / 354 km
- Cambrian Mountains, Mid Wales
What is the difference between Longest and Largest River?
Longest: travels the farthest, covers the greatest distance from source to mouth
Largest: widest river, carries the most water from the source to the mouth
Why are rivers important?
Rain fills rivers - rivers feed water to our houses
Rivers provide a source of transport in order to distribute goods to trade.
Water cycle
Collection - Evaporation - Condensation - Clouds - Precipitation - Infiltration - Percolation - Throughflow - Collection
Collection - Evaporation - Condensation - Clouds - Precipitation - Transpiration - Collection
Collection - Evaporation - Condensation - Clouds - Precipitation - Surface run off - Collection
Watershed
The edge of highland surrounding a drainage basin. It marks the boundary between two drainage basins.
Source
The beginning or start of a river.
Tributaries
a stream or smaller river which eventually joins a larger stream or river.
Confluence
The point at which two rivers or streams join.
River Channel
The main body of water in a river.
Mouth
The point where the river comes to the end, usually when entering a sea.
Landforms:
Upper - Middle - Lower
Upper: Interlocking Spurs, Waterfalls, Gorges
Middle: Meanders, Ox Bow Lakes, Floodplains, Levees
Lower: Estuaries, Deltas
Hydraulic Action
Fast flowing water that wears away the river bank underneath
Attrition
Rocks bring carried by the river, it gets smashed together, creating smaller rocks
Abrasion
rocks carried along by the river wear down the river bed and banks (eraser being used overtime)
Corrosion
smaller particles are dissolved into the river (sugar in tea)
What is a Hjulstrom Curve
the relationships between erosion, transportation, and deposition of sediments
What is a Hjulstrom Curve
the relationships between erosion, transportation, and deposition of sediments.
What are interlocking Spurs?
- erodes vertically / downwards
- created V-shaped valleys with steep sides and narrow valley floors.
- river doesn’t have enough power to erode/cut through the hills so it winds around them
- tectonic plates that move
How are waterfalls made?
- Steep drop
- Hard rock = – dolerite, unable to erode flat and a step forms
- Less resistant rock = limestone, erodes quicker, undercutting the rock above.
What are gorges?
When the waterfall retreats after the overhanging hard rock collapses, it leaves a near vertical steep sided valley. This is known as a gorge.
Waterfalls description
- Hard rock on the surface
- Fallen rocks from the over hand on the river floor
- Plunge pool, bottom of the waterfall
- Hard and soft rock below the river, making it uneven. creating rapids
What is a meander?
Bend/loop in the course of a river
How is a meander formed?
Fast flowing current that makes the land erode on the outside bend and the inside making deposition
What is an Oxbow lake?
A lake that formed using the neck of a meander.
How is an Oxbow lake formed?
Erosion makes the neck of the meander narrow then during floods, river takes the shortest course through the neck. Soon the meander will create the new and straighter course. Then itself of creating a new lake, an oxbow lake.
What are the damages of floodplains
- Damaged properties, crops: Loss od income and food supply
- Trapped elderly
- Road closed and blocked: Loss of income and education
How do levees form?
A levee is formed by deposition on the floodplain.
What are levees?
What are levees are a wall that blocks water from going where we don’t want it to go
Order of the river
Source - Tributaries - Confluence - River Channel - Mouth
