Rates of
Weathering
Lubov McKone
Lauren Brooksby
Andrew Beebe
Stephanie Zuritis
The Rate of Weathering
• The rate of weathering is the speed at
which rock or soil is broken down.
Grand Canyon- 5-6
million years of
weathering
Niagra Falls- 12,000
years of weathering
Zion Canyon200 million
years of wind
erosion
Rock Composition
• The more soluble the minerals are that
compose the rock the faster the rock
will weather.
Rock
Salt
Granite
Limestone
Mica
Topography
Topography affects the rate of
weathering because if you have rough
steep slopes, there is more area
expose to rain, wind… Therefore,
because of what we have learned
from surface area, we know that
steeper slopes with weather faster
than a flat area.
Other Things That Affect The
Rate Of Weathering
• Plants and animals can affect the rate of
weathering because if you are in a place where
there are lots of plants and animals, they will
be walking, digging, burrowing and doing
many things that would make rocks weather.
So if you are in an area with more animals
and plants, the rocks may weather faster.
Amount of Exposure
(surface area)
 When a rock is broken into smaller pieces, usually through mechanical
weathering, the surface area of the rock is increased, creating more surfaces
to weather. This will increase the rate of weathering of the rock.
For example,
these broken
up halite
crystals will
weather much
faster than this
full halite 
crystal.
Climate
Rocks weather fastest in a hot, wet, climate
This hot, arid climate has more
weathering that is caused by wind
(slower)….
Whereas weathering in this wetter
climate depends more on water
(faster)
Rock Composition
The Rock Salt composition is
halite which can dissolve in
water more easily.
Limestone is composed of calcite
which will dissolve slower in
water than the Rock Salt.
Surface Area
As a rock is broken up into more pieces the
surface area of the rock increases. Which then
lets mechanical and chemical weather more
sides.