The process of Rejuvenation & its landforms Flashcards
1
Q
Explain the process of Rejuvenation and its landforms.
A
The process:
Rejuvenation allows a river to resume vertical erosion:
A river is said to be rejuvenated if its base level is lowered. This can be caused by either the ground level rising (crustal uplift) or by a drop in sea level.
The drop in base level gives the river greater potential energy, increasing its vertical erosion potential.
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 landforms:
There are distinctive landforms associated with rejuvenation:
- River terraces are former flood plains which have been left above the level of present-day flooding following increased vertical erosion.
- Incised meanders are formed when a river keeps its meandering course as vertical erosion increases. The result is a deep, winding valley with steep sides. The river is left far below the level of the former flood plain.
