Types of Rock
Igneous Rock
How does it form?
Rock that has formed from the cooling and
solidification of magma or lava.
Igneous Rock
Two Kinds of Igneous Rock:
• Intrusive: Form from slowly cooling magma
within the Earth’s surface.
• Large Crystals
• Rough Texture
• Extrusive: Form from quickly cooling lava on
the Earth’s surface
• Small Crystals
• Fine Texture
Igneous Rock
Sedimentary Rock
• Rock formed from the compaction and
cementation of sediments or from the
precipitation of minerals in a solution.
• Compaction – squeezing together
• Cementation – gluing, sticking together
What is sediment?
• Sediments are fragments of rock that have
been broken down as a result of
weathering (wind, ice, running water, etc.)
Sedimentary Rock
• Sediments are classified according to their size.
Clay
Silt
Sand
Pebble
Cobble
Boulder
Clastic Sedimentary Rock
• The word clastic comes from Greek work,
meaning “broken”
• Formed from particles of rock (clay, silt,
sand that have been compacted together.
Clastic Sedimentary Rock
• Shale formed from fine sediments, (i.e., clay or silt).
Clastic Sedimentary Rock
• Sandstone formed from medium-size sediments,
(i.e., sand).
Clastic Sedimentary Rock
• Conglomerates formed from large pebble-size
sediments.
Nonclastic Sedimentary Rock
• Formed by chemical precipitation or
by organic activity
• Salt rock formed by evaporation
• Limestone formed by chemical precipitation or
organic activity
Nonclastic Sedimentary Rock
• Limestone
Fossils
• Sedimentary rocks are the only type of rocks
that may contain fossils, or evidence of past life.
Metamorphic Rock
• Rock formed from a change that
has occurred as a result of
exposure to intense heat and/or
pressure.
Metamorphic Rock
•Two types of
metamorphism
1. Contact metamorphism
2. Regional metamorphism
Contact metamorphism
• Involves existing rocks coming into contact with
really intense heat (i.e., lava / magma).
Regional Metamorphism
• Involves existing rocks experiencing extreme pressure as a
result of being pushed together by two converging plates.
Regional Metamorphism
Types of Rock Brochure Project
• Your brochure must include the following
pages:
• Title Page (e.g., Three Types of Rock) with Name
• Contents Page (How the rocks form)
• Provide a definition for each type of rock.
• Rock Type #1: Igneous Rock
• Rock Type #2: Sedimentary Rock
• Rock Type #3: Metamorphic Rock
• Provide a title for each page of the
rock type.
• Each page should include information
that is specific to that type of rock.
Igneous Rock
• Two Kinds of Igneous Rock:
• Intrusive: Form from slowly cooling magma within
the Earth’s surface.
• Large Crystals
• Rough Texture
• Extrusive: Form from quickly cooling lava on the
Earth’s surface
• Small Crystals
• Fine Texture
Sedimentary Rock
• Two Kinds of Sedimentary Rock:
• Clastic: Form from particles of rock (e.g., clay,
silt, and sand)
• Compacted Sediments
• Nonclastic: Form from chemical precipitation
or by organic materials.
Metamorphic Rock
Two Types of Metamorphism:
• Contact Metamorphism: Involves
existing rocks coming into contact with
really intense heat (i.e., lava / magma).
• Regional Metamorphism: Involves
existing rocks experiencing extreme
pressure as a result of being pushed
together by two converging plates.