Transcript THE ROCK CYCLE

THE ROCK CYCLE
Important terms
Weathering
The breakdown of
rock into smaller
pieces
 There are two big
categories of
weathering

Mechanical Weathering

Breakdown of rock into smaller pieces by
physical means (by force)
Mechanical Weathering

Mechanical Weathering Video
Mechanical Weathering
Ice

Water that seeps into cracks in a rock
freezes and expands, breaking the rock
http://www.phschool.com/atschool/science_activity_library/weathering_freezing.html
Abrasion

The action of rocks and sediments grinding
against each other that is caused by:
i). Wind blowing sand/sediments across rocks
ii). Water causes rocks to bump along each
other in a river or stream
iii). Gravity causing a landslide
Plants

Plant roots enter
cracks in rocks and
push the rock apart
over time
Animals

Creatures like
earthworms, ants,
and moles move
sediments around,
exposing them to
the weather
Chemical Weathering

Chemical Weathering Video
Chemical Weathering
Chemical breakdown (at a molecular level)
of rocks and minerals into new substances
 This type of weathering is caused by:

Water

Over time, water
gradually dissolves
many minerals
Acid



Acid precipitation = rain that
contains acids due to pollution;
breaks down rocks
Acid in ground water = some
locations have weak acids in
groundwater that can break
down limestone and form caves
Acid in living things = lichens
produce acids that break down
rocks
Air

Oxygen in the air
can cause rocks
containing iron to
form rust (iron
oxide)
EROSION
The breakdown and transport (movement)
of sediments, rocks, and minerals
 Erosion is caused by 4 major factors:

Wind
The blowing of
sediments (typically
small particles like
sand)
 Can cause sand
dunes to form

The Power of Wind

https://www.youtube.com/watch?v=PQmon7
Rj6ns
Water



Ocean waves change the
coastline
Streams and rivers move
sediments
https://www.youtube.co
m/watch?v=ofhQvAu_
L1I
The Power of Waves

https://www.youtube.com/watch?v=zUh3WeilFN4&li
st=PLYfqHMNCuerqq14wfEXMH9l8JTHXjJIr&index=2
Ice

Glaciers (enormous
mass of moving ice)
can move large
amounts of rock
The Power of Ice

https://www.youtube.com/watch?v=IScnw7nt2
Sw
Gravity


Can cause rocks to shift in landslides or more
slowly anywhere the ground isn’t level
https://www.youtube.com/watch?v=T5wBd
Z1x8rE
DEPOSITION
Takes place when the sediments moved by
erosion finally settle
 Typically occurs on the ocean bottom, a
lake bottom, or the base of a
hill/mountain

To Sum Up:

https://www.youtube.com/watch?v=lyysL02Zv
Q8