Long Profile Flashcards
What does long profile show about erosion?
Vertical erosion dominated in the initial stages as more water is added the river has a greater volume and increased velocity giving it more power to erode laterally.
The gradient flattens out to create concave long profile.
How are irregularities in the gradient represented?
Rapids, waterfalls or lakes.
What are knickpoints?
Marked breaks or changes in slope
What are knickpoints the product of?
Rejuvenation
When does rejuvenation occur?
When the sea level (in relation to the land) falls or when the land surface rises.
What happens during rejuvenation?
The river revives its erosion activity in a vertical direction. The river adjusts to the new base level, at first in its lowest reaches, and then progressively inland.
What creates variations in the concave profile?
Variations in rock structure- these are effects of glaciations and rejuvenation.
What does long profile present?
The changes in the altitude of the course of the river from its source, along the entire length of its channel, to the river mouth.
