Weathering, Erosion,
Deposition Intro Notes
Weathering is the breakdown of rock or
soil.
 Physical weathering occurs when natural
forces, such as wind, running water, and
moving ice, physically break up rock and
soil into smaller particles.
 For example, large moving masses of ice
called glaciers grind rock up as they
slowly slide across it.

Physical Weathering
Chemical weathering occurs when rock
and soil break down as a result of
chemical reactions.
 For example, slightly acidic groundwater
reacts with limestone to break the rock
down, leaving holes in the rock.

Chemical Weathering
Over long periods of time, biological
activity within some weathered materials
produces new soils.
 Other weathered materials are removed
by natural forces and transported to new
locations, where they eventually form new
landforms or become sedimentary rock.

Weathering
Erosion
Erosion is the transport of weathered
materials from one place to another by
natural forces.
 For example, the force of running water in
a river picks up weathered sediment and
carries it downstream.
 Very often, a natural force both weathers
and erodes the same rock or soil.

Erosion
Deposition
Deposition occurs when natural forces
lay eroded sediment down in new places.
 For example, desert winds that weather
and erode sand from one place will
deposit it to form sand dunes in another
place.

Deposition
Processes in the Rock Cycle



The rock cycle would not function without the
processes of weathering, erosion, and
deposition.
All three of the major types of rock are
broken down by weathering, carried away by
erosion, and dropped in new locations by
deposition.
The result is that sediment eventually build
up at certain locations, and is ready for form
new rock.
Rock Cycle and Processes
Please
Remember
that you
have a Test
on the
Earth’s
Layers, Rock
Cycle, and
these Notes
on Friday!
The End!