Download Geology

Geology
Earth Chemistry
Minerals
Rocks
Matter
• Matter – anything that has mass and takes
up space
• States of matter – basic forms in which
matter exists, including solid, liquid, gas, and
plasma
Matter
• Property – characteristics that describes
matter
• Physical property – characteristic of a
substance or an object that can be
observed without changing the substance
into a different substance
• Chemical property – characteristic that
describes how a substance changes into a
different substance
Properties
• Physical Properties
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Color
Shape
Size
Weight
Density
State
Taste
Feel
Smell
• Chemical Properties
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Burning
Rusting
Oxidation
Nuclear reactions
Elements
• Element – substance that cannot be
changed or separated into other kinds of
substances
• Atoms – smallest particle of an element
that has the characteristics of that element
– Ex. Carbon, oxygen, hydrogen, helium, iron,
calcium, sodium are atoms and elements
– Difference is that an element can be visible,
but an atom is not
Atoms
• Contain a nucleus, the center of the atom ,
which is made of protons and neutrons
• Electron orbitals, or energy levels, are located
on the outside of the nucleus where the
electrons are located.
Compounds and Mixtures
• Compound –
• Mixture – two or more
substance formed
elements mixed together,
when the atoms of two
but not joined chemically
or more elements join • Two substances
chemically
dissolved in one another;
• Two chemically unique
can be separated
substance join to form
naturally
a new substance;
• Salt + Water = salty
cannot be separated
water
naturally
• 2Na + Cl2  2NaCl
Compounds
• Chemical bond – sharing or transfer of
electrons between two or more atoms
• Formulas for compounds are used to
represent compounds
1. Identify the elements by their symbol
2. Determine the number of atoms of
each element.
H2O, NaCl, Fe2O3, NaHCO3, CaCO3
Minerals
• Solids
• Formed naturally in the Earth
• Have the same chemical makeup
throughout
• Not alive or made of living things
• Have definite atomic patterns
• Can be found as pure elements, such as
gold and sulfur, or compounds, such as
quartz and gypsum
Minerals
• Found in rocks, sand, soil, and seashells,
mostly beneath the Earth’s surface
• Found dissolved in water
• Mined through strip mining or deep earth
mining
• Deposits need to be refined, separated
from the rock and purified.
Quartz
Sulfur
Diamond
Calcite
Magnetite
Gypsum
Properties for Identification
• Color – different colors are used to identify
the various minerals. Some minerals may
have more than one color
• Luster – how a mineral reflects light;
metallic luster (shiny) and nonmetallic
luster (dull)
• Streak – color of the mark a mineral
makes on white tile (streak plate)
Properties for Identification
• Hardness – ability of a mineral to resist being
scratched (Mohs’ scale, 1 to 10)
• Crystal shape – basic shape that a mineral
tends to take (cubes, six sided, etc.)
• Cleavage – ability to split along flat surfaces
– Fracture: jagged break pattern
• Specific gravity – mineral’s weight compared
to the weight of water
– Specific gravity = weight of sample/weight of H2O
Common Uses
• Minerals can be changed to do a specific
job
• Minerals used to conduct electricity
• Minerals used in household items, such as
pencils, silverware, hardware, and
toothpaste
• Minerals used to make glass, circuits, and
cans
• Minerals can be used for jewelry, such as
gold silver, diamond, topaz and garnet.
Rocks
• Rock – natural, solid material made of one
or more minerals
• Igneous rock – rock formed from melted
minerals that have cooled and hardened
• Metamorphic rock – rock that has been
changed by intense heat, pressure, and
chemical reactions
• Sedimentary rock – rock formed from
pieces of other rock and organic matter
that have been pressed together
Granite (igneous)
Conglomerate (sedimentary)
Schist (metamorphic)
Igneous Rock
• Form from cooling magma, hot liquid rock
inside the Earth
• Intrusive rock – igneous rock that forms
underground from cooling magma
– Texture: size of crystals in an igneous rock
• Extrusive rock – igneous rock that forms
from cooled lava, magma that reaches the
surface, on the Earth’s surface
Igneous Rock
Granite (intrusive igneous)
Obsidian (extrusive igneous
Sedimentary Rock
• Sediment – solid material, such as sand,
soil, pebbles, and organic matter, that is
carried in air, water, or ice and settles out
• Compaction – pressure applied to
sediments
• Cementation – mixing and hardening
together of sediments
Sedimentary Rock
• Clastic rock – sedimentary rock made
mainly from fragments of other rocks
– Conglomerate: clastic rock made of round
pebbles cemented together
• Chemical rock – sedimentary rock that
forms from chemicals dissolved in water
– Limestone, rock salt, gypsum
• Organic rock – sedimentary rock that
forms from the remains of living things
– Coal, limestone, chalk
Conglomerate
Coal
Limestone
Metamorphic Rock
• Form from heat and pressure inside of the
Earth
• Foliated rocks – metamorphic rock in
which minerals have been rearranged into
visible bands
• Nonfoliated rocks – metamorphic rock that
does not show bands.
Slate (folliated)
Marble (nonfolliated
Rock Cycle
• Series of natural changes that cause one
type of rock to become another type of
rock
• Heat and pressure change rock into
various forms
• Compacting and cementation will create
sedimentary rock
• Weathering and erosion, breaking apart of
rock, will make sediments
Rock cycle