Transcript Chapter 4 Rocks: Mineral Mixtures

Chapter 4
Rocks: Mineral Mixtures
Standard S6E5.b
Investigate the composition of rocks in
terms of minerals
EQ: How are rocks and minerals
different?
Section 1 pp.90, 95, 96
• Rock
• Naturally occurring
solid mixture of one or
more minerals and
organic (living) matter
• What is the Rock Cycle?
• Past uses for Rocks
• Used to make…
• The series of processes
in which a rock forms,
changes from one type to
another, is destroyed,
and forms again by
geological processes.
• Include hammers to make
other tools
• Make ancient and
modern buildings &
monuments
• What is weathering?
• Why is it important?
• What is Erosion?
• What is deposition?
• The process in which water,
wind, ice & heat break down
rocks
• It breaks down rock into
fragments. This is the
sediment from which
SEDIMENTARY rocks are
made.
• Erosion is the process by
which wind, water, ice, or
gravity transports soil &
sediment from 1 location to
another.
• Deposition is the process in
which material is laid down.
– Sediments may be pressed
& cemented
EQ: What is Uplift?
• What is uplift?
• What happens when
uplift reaches the
Earth’s surface?
• It is movement within
the Earth that causes
rocks inside the Earth
to be moved to the
Earth’s surface
• Weathering, erosion,
and deposition begin
EQ: How are rocks classified?
• 3 Classes of Rocks
1. Igneous
2. Sedimentary
3. Metamorphic
Rocks are classified by:
• Composition
• The chemical makeup of
the rock –the minerals
and other materials
• Texture
• The size, shape and
positions of the rock
grains
• Provides clues as to how
and where the rock is
formed
Warmup
• Write a paragraph that:
• Compares and contrasts minerals and
rocks.
EQ: Where do igneous rocks
come from?
Section 2: pg. 98-101
• Igneous Rocks
• Igneous means “fire”
• Begins as magma
that contains many
minerals
• Cooled magma
hardens and solidifies
(becomes a solid)
Igneous Rock Composition
• Composition of Igneous
Rocks
• Determined by minerals
• Light colored ones – less
dense– made of
aluminum, silicon-Felsic
Rocks
• Dark colored ones – more
dense, made of iron,
calcium, & magnesiumMafic Rocks
Igneous Rock Texture
• Texture of Igneous Rocks
• Size of the grains
• Fast cooling lava on the
surface of the volcano -fine grains or no
grains Ex: pumice
• Slow cooling magma
inside the Earth -large grains
Ex: granite
Igneous Rock Formation
• Igneous Rock
Formation
• Intrusive igneous rock
– forms inside Earth
– cools slowly
– Many are named for
their size & shape
– Large (coarse) grains
• Ex: granite
• Igneous Rock
Formation
• Extrusive Igneous
Rock –
– forms on Earth’s
surface
– Common around
volcanoes
– cools fast
– fine grains or no grains
Ex: pumice
• Igneous Rock
Formation
• In other words, the
faster the magma or
lava cools the smaller
the grains of the rock
• The slower the
magma or lava cools
the larger the grains
of the rock
Summary
• Compare and contrast Stone Mountain’s
granite and pumice from a volcano.
Draw a Picture of the Formation of
Igneous Rocks
• Label intrusive, extrusive, magma, lava.
• Show the grain size of the developing
rocks.
• Indicate how fast the rocks cool.
• Name rock samples for each class of
igneous rocks.
EQ: What are sedimentary rocks
made of?
Section 3 pg. 102 – 105
• Sediments
• Fragments of
weathered rock &
minerals
• Strata
• Layers of sedimentary
rock on Earth’s
surface that forms
when the sediment is
deposited &
cemented together by
dissolved clacite &
quartz
• Stratification
• Process in which
sedimentary rocks are
arranged in layers
• What do they record?
• Motion of wind &
water waves on
oceans, rivers, and
sand dunes
EQ: What are the 3 classes of
sedimentary rock?
• Clastic
• Made of rock
fragments cemented
together by dissolved
calcite & quartz
• May be any grain size
• Examples:
conglomerate, shale,
sandstone
• Chemical
• From solutions of
dissolved minerals in
water
• The dissolved
minerals crystallize
• Ex: halite—salt—
NaCl Result of
supersaturated salt
water
• Organic
• Made from the remains of
dead organisms
• Ex: Chalk is made of tiny
sea creatures
• Ex: Coal forms
underground when
decomposed plant
material is changed into
coal by heat & pressure
Fossil fuels are nonrenewable resources
Summary
• Describe the formation of the 3 classes of
sedimentary rock.
• Draw a picture of how each sedimentary
rock forms
• Show the rock “before” it became a
sedimentary rock and the “after” or the
resulting sedimentary rock.
• Label each class of sedimentary rock.
• Compare and Contrast Igneous and
Sedimentary Rocks
EQ: What is metamorphism?
Section 4 pg. 106 – 111
• Metamorphism
• Change shape
• Metamorphic Rock
• The structure, texture
or composition of the
rock changes
because of extreme
heat and/or pressure
• A chemical change
occurs
• Deformation
• Change in the shape
of a rock caused by a
force, like squeezing
or stretching
EQ: What are the 2 classes of
metamorphic rock?
• Foliated
• Mineral grains are
arranged in bands
• Ex: mica, slate
• Non-foliated
• Random arrangement
of grains
• Commonly made of 1
or a few minerals
• Ex: marble
Summary
• If I needed to make a tool from a rock,
should I choose a foliated or a non-foliated
metamorphic rock? Explain your answer.