Download Weathering


Weathering is the process by which rocks break
down and change
 Mechanical
 Chemical
Mechanical(Physical) Weathering is the process
where rocks break into smaller pieces with no
change in their composition
 Caused by:
 Cold temperatures
 Tectonic Processes
 Biological Activity


Frost Wedging-The
repeated thawing and
freezing of water in the
cracks of rocks
 Water expands when
frozen, chips away
parts of the rock
Unloading occurs
when igneous rock
becomes exposed
through uplift and
erosion
 Exfoliation-Occurs
when pieces of the
uplifted rock are
weathered and
chipped away


Organisms can cause
Mechanical Weathering
 Plant roots growing
into cracks in rocks
 Burrowing animals
moving rocks
 Decayed animals can
produce acids
(Chemical
Weathering)


Chemical Weathering- Rocks undergo
changes in their composition
Caused by:
 Water
 Oxygen
 Carbon Dioxide
 Acids


Hydrolysis-The
reaction of water
with other
substances
Oxidation-The
reaction of oxygen
with other
substances

Water causes Chemical Weathering by absorbing gases
from the atmosphere and ground
 CO2 +Water  Carbonic Acid
▪ Dissolves Rocks/Minerals
▪ Stalactites/Stalagmites

Differential weathering is when rocks
weather at different rates
 Caused by different mineral compositions
 Sedimentary rocks weather more easily
than igneous rocks


The statue of liberty is made
of copper which is generally a
brownish color
Has been affected by chemical
weathering
 Water reacting with the copper
 Sulfuric acid formed by pollution
(debatable)