Rocks and
The Rock
Cycle
3 Main Rock Types
Igneous
Sedimentary
Metamorphic
3 Main Rock Types
Igneous
Sedimentary
Metamorphic
Igneous
EXTRUSIVE
Forms when lava cools
quickly on the Earths
surface
Forms from molten
rock cooling and
solidifying
INTRUSIVE
Magma cools slowly
over millions of years
deep beneath the
surface
Igneous
EXTRUSIVE
Forms when lava cools
quickly on the Earths
surface
Forms from molten
rock cooling and
solidifying
INTRUSIVE
Magma cools slowly
over millions of years
deep beneath the
surface
IGNEOUS---Extrusive
Little or NO Crystals!
Lava cools on
the surface so
fast mineral do
not get a
chance to form
Extrusive rocks
can be divided
into two
categories
based on color
Dark colors
black-brownred
Light colors
white-gray-pink
• Basalt
• Obsidian
• Rhyolite
IGNEOUS---Extrusive
Little or NO Crystals!
Lava cools on
the surface so
fast mineral do
not get a
chance to form
Extrusive rocks
can be divided
into two
categories
based on color
Dark colors
black-brownred
Light colors
white-gray-pink
• Basalt
• Obsidian
• Rhyolite
IGNEOUS---Extrusive
Little or NO Crystals!
Lava cools on
the surface so
fast mineral do
not get a
chance to form
Extrusive rocks
can be divided
into two
categories
based on color
Dark colors
black-brownred
Light colors
white-gray-pink
• Basalt
• Obsidian
• Rhyolite
IGNEOUS---Extrusive
Little or NO Crystals!
Lava cools on
the surface so
fast mineral do
not get a
chance to form
Extrusive rocks
can be divided
into two
categories
based on color
Dark colors
black-brownred
Light colors
white-gray-pink
• Basalt
• Obsidian
• Rhyolite
Igneous
EXTRUSIVE
Forms when lava cools
quickly on the Earths
surface
Forms from molten
rock cooling and
solidifying
INTRUSIVE
Magma cools slowly
over millions of years
deep beneath the
surface
IGNEOUS---Intrusive
Large Interlocking Crystals!!!
Magma cools
slowly over
millions of
years…
LARGE CRYSTALS
FORM
Intrusive rocks
can also be
divided into two
categories based
on color
Dark colors blackbrown-green
Light colors
white-gray-pink
• Gabbro
• Granite
IGNEOUS---Intrusive
Large Interlocking Crystals!
Magma cools
slowly over
millions of
years…
LARGE CRYSTALS
FORM
Intrusive rocks
can also be
divided into two
categories based
on color
Dark colors blackbrown-green
Light colors
white-gray-pink
• Gabbro
• Granite
IGNEOUS---Intrusive
Large Interlocking Crystals!
Magma cools
slowly over
millions of
years…
LARGE CRYSTALS
FORM
Intrusive rocks
can also be
divided into two
categories based
on color
Dark colors blackbrown-green
Light colors
white-gray-pink
• Gabbro
• Granite
IGNEOUS---Intrusive
Large Interlocking Crystals!
Magma cools
slowly over
millions of
years…
LARGE CRYSTALS
FORM
Intrusive rocks
can also be
divided into two
categories based
on color
Dark colors blackbrown-green
Light colors
white-gray-pink
• Gabbro
• Granite
3 Main Rock Types
Igneous
Sedimentary
Metamorphic
How to make a clastic
sedimentary rock
Weathering and
Erosion
Transportation
Compaction and
Cementation
Deposition
Sedimentary
Rock
Sedimentary
Sedimentary rocks are
divided into two categories
Chemical
Clastic
Mineral are dissolved in to the
water…water is evaporated off
and leaves behind chemical
sedimentary rocks
Made from eroded
fragments of other
rocks
Examples are
Halite,
Limestone and
Gypsum
Shale
Microscope grains
of mud cemented
together
Sandstone
Sand grains
cemented together
Conglomerate
Pebble to boulder
size fragments
cemented together
3 Main Rock Types
Igneous
Sedimentary
Metamorphic
Metamorphic rocks form from
HEAT&PRESSURE
Two types of
metamorphism
Contact
Rock surrounding
a magma body get
cooked and
changes due
Regional
Tectonic forces
Metamorphism
occurs over a large
area
Contact Metamorphism
Deep underground, zones of metamorphism form around the hot magma
of batholiths.
L.Gardiner/Windows Original
Regional Metamorphism
Tectonic forces smash continents together. The rocks get heated and
become semi-molten. The added pressure causes the mineral to
separate into bands and sometime to even flow before cooling again!
Common Metamorphic Rocks
Parent Rock
Metamorphic Rock
Granite
Gneiss
Shale
Slate
Sandstone
Quartzite
The Rock Cycle