AQA AS Geography Rivers: Rejuvenation

HideShow resource information
  • Created by: LucySPG
  • Created on: 22-08-13 20:11
Preview of AQA AS Geography Rivers: Rejuvenation

First 195 words of the document:

Rejuvenation
Rejuvenation is when there is a fall in the base level of a river basin.
Base level: is the lowest point to which erosion by running water can occur
This can be caused by either the ground level rising or by a drop in sea level.
Climatic change: Glaciations and changes in rainfall
Tectonic change: Where land is uplifted after plate movement or volcanic
activity. Changes can be positive sea level rises in relation to
the land, or negative sea level fall in relation to the land
Sea level change can be either:
Isostatic: increase in relative height of land in relation to the sea
Eustatic: fall in sea level
The drop in base level gives the river greater potential energy, increasing its vertical erosion
potential.
Knickpoint
The long profile of the river is extended and a knickpoint ­ a sharp change in gradient, often
a waterfall ­ will form and mark the junction between the original long profile and the new
one.
The knickpoint is the point at which the river used energy to correct itself.

Other pages in this set

Page 2

Preview of page 2

Here's a taster:

River Terrace
River terraces are former floodplains which have been left above the level of present-day
flooding following increased vertical erosion.
They are also commonly chosen as sites for human settlement because they are safe from
flooding.
Many towns and cities throughout the world have been built on terraces, including London,
which is built on the terraces of the River Thames.
Incised Meanders
If land is uplifted for a considerable period of time a river may cut downwards and form
incised meanders.…read more

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all resources »