rivers - river processes

1. 1. sorry this is at the coast but it's the same principal
2. the force of a river against the banks can cause air to be trapped in cracks and crevices. the pressure weakens the banks and gradually wears it away

2. stones that have just entered the river are large and jagged. As transportation occurs the stones collide with each other and knock off each others jagged sides making them smaller and more spherical. The further they travel the more this occurs.

2. sometimes called corrasion
3. small load scratch and scrape their way down a river during transport, this wears down the banks and bed of the river channel

2. also called corrosion
3. the dissolving of rocks such as limestone or chalk
   1. this could be the load itself

1. all shapes and sizes
2. all different materials
3. rocks fallen ito the river or the river banks and bed that have been eroded

2. large or heavy load is rolled along the river bed
   1. not necessarily heavy load, it could be that the rivers velocity is not big enough
   2. load carried in this way is called bedload

2. Small pebbles and stones are bounced along the river bed. When velocity increases they are picked up, when it decreases they are deposited.

1. fine light material such as alluvium is held up and carried within the rivers flow
   1. this is called suspended load

Anmerkungen:

• yes, again

2. minerals are dissolved in the water
   1. this is a chemical change to rocks such as limestone and chalk
   2. load carried in this way is called solute load

1. this explains why mountain streams have boulders along their bed while there is only fine silt near the mouth