Landforms of Fluvial Erosion and Deposition

Description

A-Level Geography (Rivers) Flashcards on Landforms of Fluvial Erosion and Deposition, created by Isobel Wagner on 12/04/2015.
Isobel Wagner
Flashcards by Isobel Wagner, updated more than 1 year ago More Less
Holly Hughes
Created by Holly Hughes about 10 years ago
Isobel Wagner
Copied by Isobel Wagner about 10 years ago
2
0

Resource summary

Question Answer
Formation of a Waterfall ・hard rock overlays soft rock ・less resistant rock erodes faster (by abrasion and hydraulic action) leaving an elevated platform of hard rock ・the process continues to create an undercutting with a plunge pool at the base ・rocks that fall into pool become erosive tools in the formation of a gorge after continual retreat
Formation of Potholes ・water flows over the bed load ・the sediment erodes the bed by abrasion causing depressions ・rocks get trapped in the depressions and become erosive tools, they swirl with the turbulent flow in eddies to deepen the depressions into potholes ・this is common in plunge pools due to the very turbulent flow
Formation of Meanders ・Are formed due to lateral erosion and deposition. ・Due to the force of the water and the greater energy on the outer bend, it erodes and undercuts the river bank. ・On the inner bend since it has a slower flow and more friction the material is deposited . ・The inside produces a beach and the outside a cliff. ・Overall it produces large s shaped bends in the rivers channel.
Formation of Braided Stream ・Braiding is common in streams with variable discharge and the load is large ・Rivers with a high load and low velocity cause rivers to become clogged ・this is because discharge falls and capacity and competence are reduced ・the sediment which clogs the channel causes it to converge and diverge into sections. ・islands of deposition which the channel moves around are called eyots
Formation of a Floodplain ・large flat areas of land located on either side of the river ・meanders migrate due to lateral erosion which flattens the land ・when the river floods, the friction is large and velocity falls causing deposition ・the sediment deposited is silt and alluvium which is very fertile
Formation of Levees ・water overflows its banks and there is a decrease in velocity due to friction ・Hjulstrom's Curve says large particles are deposited first and smaller particles spread further ・the continual process increases the height of the river and is a natural prevention of river flooding
Formation of Deltas ・the river velocity and competence decrease as the river reaches the mouth ・they only form when deposition exceeds sediment removal (erosion) ・when the fresh water of the river and the salt water of the sea meet, there is an electrical charge ・this causes clay particles to coagulate in a process called flocculation ・the particles sink clogging the pathway to the sea causing the river to enter in different pathways
Show full summary Hide full summary

Similar

Water on Land Keywords
Adrian Ridley
Introduction to Rivers for Junior Cert - Important Definitions of Key Terms
Gaeilge SPC
Drainage basin and definitions (+ water balance etc)
Alice Kimpton
Coastal Development and physical processess
Corey Meehan
Geography Coastal Zones Flashcards
Zakiya Tabassum
Tectonic Hazards flashcards
katiehumphrey
GCSE Geography - Causes of Climate Change
Beth Coiley
Volcanoes
1jdjdjd1
The Rock Cycle
eimearkelly3
Plate Tectonics
eimearkelly3