deposition and sedimentation - The Hjulstrom curve Flashcards
1
Q
causes of deposition
A
a shallowing gradient, decreasing velocity and energy
decrease in the volume of water in channel
increase in froction between water and channel
2
Q
downstream fining
A
sediment gets finer with increasing distance downstream
3
Q
deposition
A
when velocity of river begins to fall, competence decreases and starting with the longest particles, the material is deposited
4
Q
The Hjulstrom curve
A
energy left after the river has overcome friction may be used to transport sediment
competence/ ability to do so depends on the velocity as shown in the Hjulstrom curve
5
Q
critical erosion velocity
A
lowest velocity at which grains of a given size can be moved. Relationship of these variables is shown by the Hjulstrom curve
