THE ROCK CYCLE
The Rock Cycle


Continuous recycling of
rocks
Shows how rocks
change from one type
to another.
3 Types of Rocks

Igneous Rocks
Melted material inside
the Earth cools
 Extrusive Rocks

Lava/Magma cools on
Earth’s Surface
 Granitic (light in color)


Intrusive Rocks
Lava/Magma cools
beneath Earth’s surface
 Basaltic (dark in color)

3 Types of Rock

Sedimentary Rocks
 Sediment
collects in
layers and compacts to
form rocks
 Take thousands to
millions of years to
form
 Contain Fossils
Sedimentary Rock

Detrtial Rocks
 Made
of grains of
minerals that have
been deposited in
layers by wind, water,
or gravity
 Siltstone, Shale,
Conglomerate,
Sandstone
Sedimentary Rock

Chemical Rocks
 Form
when mineral
water from seawater,
geysers, hot springs, or
salty lakes evaporates
 Rock Salt (not the kind
you eat)
Sedimentary Rocks

Organic Rocks
 Formed
from the
decomposition of living
matter
 Formed over millions of
years
 Chalk, coal, limestone
3 Types of Rock

Metamorphic Rock
 New
rocks that form
when existing rocks are
heated or squeezed,
but not melted
 Takes millions of years
for a change to occur
Metamorphic Rocks

Foliated Rocks
 Have
visible layers or
elongated grains of
minerals
 Slate,
gneiss, phyllite,
schist

Nonfoliated Rocks
 No
distinct layers or
bands
 More even in color
 Quartzite