Presentation on theme: "FEATURES OF EROSION & FEATURES OF DEPOSITION RIVERS."— Presentation transcript:
FEATURES OF EROSION & FEATURES OF DEPOSITION RIVERS
A Meander in a river River erodes on the outside of the bend of the meander and deposits on the inside of the bend.
Deposition The rivers speeds around the outside of the bend as it cuts its way; the water is much slower on the inside of the bend where mud and silt etc are dropped or deposited.
FEATURES OF DEPOSITION BEACHES SPITS Sea
The sea Coastal Deposition Landforms: Features and Formation Material that is transported by the waves along a coastline is eventually deposited forming distinctive deposition features.
Sea deposition Beaches and spits These are two main deposition features that you need to learn the formation of. These are: 1. Beaches 2. Spits
Features of coastal deposition The main feature of coastal deposition is the BEACH Beaches Beaches are the main feature of deposition found at the coast, these consist of all the material (sand, shingle etc.) that has built up between the high and low tide mark.
Beaches The material that makes up a beach comes from… There are number of different sources of beach material - the main source being rivers, where fine muds and gravels are deposited at the river mouth. Other sources of beach material include longshore drift (bringing material from elsewhere along the coast); constructive waves (bringing material up the beach from the sea) and from cliff erosion.
As constructive waves build up beaches, they often form ridges in the beach known as berms. The berm highest up the beach represents the extent to which the water has reached during high tide, aka the high water mark.
Spits Spits are long narrow ridges of sand and shingle which project (stick out) from the coastline into the sea. Longshore drift moves material along the coastline. A spit forms when the material is deposited (or left behind / dropped). Over time, the spit grows and develops a hook if wind direction changes further out. Waves cannot get past a spit, which creates a sheltered area where silt is deposited and mud flats or salt marshes form.
This spit is approximately 20 miles long Farewell Spit, On New Zealands South Island
FEATURES OF EROSION HEADLANDS BAYS CAVES ARCHES STACKS STUMPS Sea
Headlands and bays
Headland Bay The headland is the part that remains out in the sea The bay is the curved or scooped out space that the sea waves eroded Headlands and bays