Transcript Limestone is a sedimentary rock!

Rock Types
Igneous, Sedimentary,
Metamorphic
Igneous rocks
make up 95%
of the rocks of
the crust of
Earth. They
are also some
of the oldest
rocks that are
found at the
surface of
Earth.
Igneous rocks
form from
molten rock
which is either
ejected at the
surface of Earth
or cools off
underground.
When volcanoes
erupt, they can
eject molten
rock.
Extrusive Igneous Rock
• Extrusive means to stick out. Extrusive
rocks form when they cool at the Earth’s
surface. Because of their rapid cooling,
they have smaller crystals.
Extrusive rocks that cool quickly have
very small crystals.
Obsidian is a good example of a very quickly
cooled extrusive igneous rock. It appears glasslike.
Sometimes when an extrusive rock is
cooled very quickly and has lots of air
pockets we get pumice or scoria.
Scoria
Pumice
Intrusive rock cools under the
surface. It has more time to cool
and forms larger crystals. Quartz
Granite
Diorite
Sedimentary rocks are the result of the
processes of weathering and erosion which
are continually breaking down and
rearranging them. Small rocks, fragments
and organic remains that have been moved by
water, wind or other agents of erosion are
called sediment. Over a period of time,
sediment is cemented together.
Sandstone
Sedimentary rocks can be formed from
metamorphic, igneous or other sedimentary rocks
that have been broken down by weathering. In
nature sedimentary rocks are usually found in
layers with the oldest layer on the bottom.
Three types of Sedimentary Rocks
• Clastic: made of broken pieces of other
rocks that are squeezed and cemented
together. Sandstone
Brecci
a
Shale
Organic Sedimentary Rocks
• Remains of plants and animals.
Coal
Limestone
Chemical Sedimentary Rocks
• Dissolved minerals that crystallize by
precipitation or evaporation.
Gypsum
Halite
Limestone
Metamorphic Rock
METAMORPHIC ROCK
Has this ever happened to you?
You take a peanut butter and jelly sandwich to
school. You check your backpack at lunch and
find that your books have been sitting on the
sandwich all day! The heat of the day and
pressure of the books have mushed the
sandwich into a completely different shape.
Your lunch has experienced what rocks
experience deep in the interior of Earth, the
process of metamorphism.
Rocks that have changed shape or
composition due to intense heat and pressure
are called metamorphic rocks.
• Metamorphic rocks are created from
sedimentary, igneous or other
metamorphic rocks.
• They are formed deep inside the earth.
• Heat and pressure from the rock above
AND below flatten and bend the rock.
HEAT
&
PRESSURE
Foliated or Non-foliated
Gneiss
Slate
Phyllite
Marble
Schist
Quartzite
Shale + Heat & Pressure = Slate
Basalt + Heat & Pressure = Schist
Granite + Heat & Pressure = Gneiss
Limestone + Heat & Pressure = Marble
Sandstone + Heat & Pressure = Quartzite
Remember!
• Igneous rocks are formed by cooling of
magma, either above or below the Earth’s
surface.
• Sedimentary rocks are formed from broken
pieces of other rocks (sediment) of all sizes.
• Metamorphic rocks are other rocks that are
changed through heat and pressure.
Pumice is an igneous rock!
What kind of rock is pumice?
Igneous? Sedimentary? Metamorphic?
Quartzite is a metamorphic rock!
What kind of rock is quartzite?
Igneous? Sedimentary? Metamorphic?
Coal is a sedimentary rock!
•Is coal a mineral????
What kind of rock is coal?
Igneous? Sedimentary? Metamorphic?
Obsidian is an igneous rock!
What kind of rock is obsidian?
Igneous? Sedimentary? Metamorphic?
Halite is a sedimentary rock!
What kind of rock is halite (salt)?
Igneous? Sedimentary? Metamorphic?
Sandstone is a sedimentary rock!
What kind of rock is sandstone?
Igneous? Sedimentary? Metamorphic?
Limestone is a sedimentary rock!
What kind of rock is limestone?
Igneous? Sedimentary? Metamorphic?
Basalt is an igneous rock!
What kind of rock is basalt?
Igneous? Sedimentary? Metamorphic?
Gneiss is a metamorphic rock!
What kind of rock is gneiss?
Igneous? Sedimentary? Metamorphic?
Da Rock Cycle!