Download Rocks and Weathering

Weathering
NAME________________________
Period_____ Date______________
Notes #1- Earth Systems
Weathering
_________________________ is the process that breaks down rock and other substances
at the Earth’s surface.
Factors that contribute to weathering:
heat, cold, water, ice, O2 and CO2 in the atmosphere
smaller
The forces of weathering break the rocks into __________________ and smaller piece
Erosion -the movement of rock particles by wind, water, ice, or gravity.
wear
carry
***Weathering and erosion work together to __________ down and ____________
away the rocks at the Earth’s surface.***
Two Kinds of Weathering:
1. ___________________Physical
weathering- physically breaking down rocks into
smaller pieces.
Forces of physical weathering:


Ice wedging
Freezing and thawing- _______________________- the process that
splits rock when water seeps into cracks, then freezes and expands
Release of pressure-erosion moving material from the outside of a rock
releases pressure on rocks below causing the rock’s surface to crack and
flake off.

Growth of plants- roots grow into cracks in rocks and can pry apart
cracked rocks

Action of animals- burrowing animals can loosen and break apart rocks in
soil such as moles, gophers, prairies dogs, some insects, etc.

__________________- the grinding away of rock by rock particles carried
by water, ice, wind, or gravity
Abrasion
slowly
Physical weathering works_____________________!!
Over time, physical weathering does more than wear down rocks, it can eventually
mountains
wear away whole ____________________________!!!!!!!!!
Chemical
2. ___________________________
weathering- the process that breaks down rock
through chemical changes.
*Chemical weathering produces rock particles that have a different
mineral makeup
________________________________ from the rock they came from.
holes
soft
**Chemical weathering creates _________________ or ___________ spots in
rock, so the rock breaks apart more easily.
together
***Chemical and physical weathering often works _____________________.
As physical weathering breaks rocks into pieces, more
surface area
_________________________ becomes exposed to chemical weathering.
Agents of chemical weathering:

Water (H2O)- most important agent of chemical weathering-
dissolving
Water weathers rock by ____________________ rock.
iron
rust
oxidation
process called __________________________.

Oxygen (O2) Rock that contains __________ will ___________ in a

Carbon dioxide (CO2) CO2 becomes dissolves in rainwater and in water
that sinks through air pockets in the soil. It becomes a weak acid
carbonic acid
marble
limestone
_________________ and ____________________________.
roots push into cracks and produce
Living organisms – Plant _____________
called___________________________( H2CO3). H2CO3 easily weathers

acids
Lichens
_______________ are “pioneer” plants that are the first to grow onto
weak __________ that slowly dissolve the rock.
bare rock.

Acid rain – rain with a lower pH than normal rain. It forms from pollutants
in the air that come from t he burning of coal, oil, and gas.
Rate of Weathering- the most important factors that determine the rate are:
Type
hot and ________
wet climates have faster rates
B. Climate
______________--------- _________
A. ____________ of Rock- permeable rocks weather faster