EQ4 why Is There a Variety Of River Landscapes/processes Flashcards
What is the long profile of a river
Shows changes in the altitude of a river.
What is different between hydraulic action and abrasion
Hydraulic when rocks rub against other rocks
Abrasion rocks grinding against a rock surface
What is weathering
A way of erosion e.g. hydraulic action, abrasion, attrition etc…
Compare traction with suspension transport
Traction: rolls along larger rocks along the bottom of the river
Suspension: smaller rocks are carried through the water
How is a waterfall formed
A stream has a drop of point which is surrounded by soft rock which erodes away to form a bowl and the soft rock keeps eroding away making the harder rock on top fall and this processes carries on
How are interlocking spurs formed
As the river erodes the landscape in the upper course, it winds and bends to avoid areas of hard rock. This creates interlocking spurs, which look a bit like the interlocking parts of a zip. When a river runs over alternating layers of hard and soft rock, rapids and waterfalls may form.
How are oxbow lakes formed
After a long period of time, the meander becomes very curved, and eventually the neck of the meander becomes narrower and the river cuts through the neck during a flood, cutting off the meander and forming an oxbow lake.
How are meander formed
In the middle course the river has more energy and a high volume of water. … As the river erodes laterally, to the right side then the left side, it forms large bends, and then horseshoe-like loops called meanders. The formation of meanders is due to both deposition and erosion and meanders gradually migrate downstream.
How are leeves formed
Landforms of deposition - lower course. The formation of levees and floodplains are linked and involve repeated flooding and the build-up of material during the period of flood. Under normal low conditions, the river is contained within its banks and so no sediment is available to form levees of the floodplain.
How are deltas formed
When a river reaches a lake or the sea the water slows down and loses the power to carry sediment . The sediment is dropped at the mouth of the river. Some rivers drop so much sediment that waves and tides can’t carry it all away. It builds up in layers forming a delta.
Explain two ways climate and geology change river landscape
Impermeable rock
Deforestation
Compare a flashy and subdeud hydrograph
Subdeud: not much precipitation or peak discharge
Flashy: a lot of precipitation and high peak discharge
How can human factors affect flooding
Impermeable rock
Deforestation
How does physical and human factors affect flooding
Impermeable rock
Deforestation
Sediment in river
What are the affects in flooding of the environment
Destruction of farmland industry houses etc
Dangerous chemicals and objects in river
Loss of life
