This document discusses erosion, deposition, and the agents that cause them. It defines erosion as the movement of rock material from one place to another by various agents like wind, water, waves, gravity, and glaciers. Deposition occurs when eroded sediments are dropped in a new location as the speed of the transporting agent decreases. The main agents of deposition are wind, water, and ice, which drop sediments when they slow down. The key difference is that weathering breaks down rocks, erosion transports materials, and deposition drops the materials in a new place.

1. EROSION AND DEPOSITION
MADE BY BIBHAB SAHA
Class 7

2.  What is Erosion?
 Erosion – The moving of rock material
from one place to a new location.
Weathering has to happen before
erosion. The rocks have to be broken
into smaller sediments before they can
be eroded away

3. AGENTSOF EROSION
 Wind : This is when loose soil particles are collected by
the wind and transported to another location.
 Flowing water : Water erosion is the removal and
transportation of soil, sediment, or mineral components
of a rock by a moving, liquid water source.
 Waves : Wave erosion creates retrograde, or retreating,
shorelines with sea cliffs, wave-cut benches at the base
of the sea cliffs, and sea arches—curved or rectangularly
shaped archways that result from different rates of
erosion due to varied bedrock resistance.
 Gravity : Downward movement of rock and sediments,
mainly due to the force of gravity
 Moving Ice (glaciers) : Movement of soil or rock from
one point to another by the action of the moving ice of a
glacier. Also known as ice erosion.

4. WHAT IS DEPOSITION?
 Deposition– It is the process where sediments
are released/dropped by their agent of erosion
 Process of erosion stops:
-when the moving particles fall out of the
transporting medium and settle on a surface
– Speed of the medium slows or the resistance
of the particles increases, the balance changes
and causes deposition
– Speed can be reduced by large rocks, hills,
vegetation, etc.

6. AGENTS OF DEPOSITION
 Wind : All the sediment picked up by wind eventually
falls back to the ground. This happens when the wind
slows down or some obstacle, such as a boulder or a
clump of grass, traps the windblown sand sediment.
 Water : As water moves, it carries sediment with it.
Anytime moving water slows down, it drops, or deposits,
some of the sediment. As the water slows down, fine
particles fall to the river's bed. Now the larger stones quit
rolling and sliding
 Ice : A glacier gathers a huge amount of rock and soil
as it erodes the land in its path. When a glacier melts, it
deposits the sediment it eroded from the land, which
creates a variety of landforms.

7. WHAT’S THE DIFFERENCE?
• WEATHERING – Think of weather
wearing rock down.
• EROSION – Think of a road and
travelling.
• DEPOSITION – Think of depositing
money into a bank.