Hi everyone,
Here are some quick references:
My website: http://www.colgate.edu/facultysearch/facultydirectory/dkeller
How to supercool water: http://chemistry.about.com/od/chemistryhowtoguide/a/how-to-supercool-water.htm
video website links:
Water to ice: http://www.youtube.com/watch?v=3Qasw7lb2UM
One I didn't have time to show you that you might like for general reference/interactive exercises:
http://www.learner.org/interactives/rockcycle/diagram.html
Sediment transport: http://www.youtube.com/watch?NR=1&v=O9GVRKnMch8&feature=endscreen
Making evaporites: http://www.youtube.com/watch?v=QwiPplYoH7Q&feature=related
I also was thinking that somebody may want to know how for instance, sulfur the mineral is different from sulfur the
element. Minerals follow the definition guidelines so the sulfur atoms would need to arrange themselves in the specific
atomic arrangement that is characteristic of the mineral sulfur to be a mineral whereas sulfur the element just needs to
have the necessary 16 protons in its nucleus.
Lastly – I wish I could have given you more sets of minerals, rocks and fossils for your classrooms but just remember, you
can find some for yourselves, just like I did by collecting the schists & phyllites when my sister and I visited a beach near her
house in CT., and like we all did with the fossils. At the Herkimer Diamond Mine, you can not only find quartz crystals but
also calcite, dolomite (usually opaque white, pale orange or pale pink) and celestite (light blue). Local rocks include shale,
graywacke, quartz sandstone, limestone. If you go to the Adirondacks you can find gneiss, marble, gabbro (high peaks. This
gabbro is actually a rock that is more specifically called "anorthosite" which is composed of almost all Ca-feldspar. There
are also amphibolites that are mostly all hornblende. So keep an eye open for some good finds! Happy Hunting! - Di
Rocks
vs. Minerals
What's the Difference?
Minerals
• naturally occurring, inorganic, crystalline solid
• ordered atomic arrangement
• definite chemical composition
2 minerals can have:
or
same composition but
different structures
ex., Graphite & Diamond (C)
same structure but
different compositions
rhodochrosite
MnCO3
Photo Copyright © 2007
Michael C. Roarke
calcite
CaCO3
http://images.tutorvista.com
siderite
FeCO3
BUT no 2 minerals have the same combination
Rocks
Aggregates of
minerals
&
Minerals
• naturally occurring
• inorganic
• crystalline solid
= ordered atomic arrangement
• definite chemical composition
Aggregates of
elements
Quartz
SiO2
K-feldspar
KAlSi3O8
Hornblende
(Ca,Na)2-3 (Mg,Al,Fe)5Si6 (Si,Al)2O22(OH)2
"Reading Rocks"
"Reading from the Great Stone Book"
Rocks = "sentences"
Minerals = "words"
Periodic Table of the Elements = the "alphabet"
(but actually only 8-10
very common elements)
Quartz
SiO2
K-feldspar
KAlSi3O8
Hornblende
(Ca,Na)2-3 (Mg,Al,Fe)5Si6 (Si,Al)2O22(OH)2
8 Elements make up 98.6% of Earth’s crust
O
Al Si
Na Mg
K Ca
Fe
Others
Si & O
account
for 74.3%
Al
Si & O
Common Mineral Classes
(based on anions in formula)
Si & O account for 74.3%
Silicates are the most abundant
Chemical formula contains Si & O
Native Elements- formula contains one element
Oxides - formula contains O (but no Si, C, S)
Hydroxides - formula contains OH
Carbonates - formula contains CO3
Sulfides - formula contains S
Sulfates - formula contains SO4
Phosphates - formula contains PO4
Halides - formula contains Cl, F, I, or Br
(halogen elements)
Common Mineral Classes
(based on anions in formula)
Examples of Silicates:
Chemical formula contains Si & O
The most common mineral: Quartz SiO2
The most common group of minerals: Feldspars:
Orthoclase KAlSi3O8
Albite NaAlSi3O8
Anorthoclase CaAl2Si2O8
Examples of Other Common Mineral Classes
Native Elements - formula contains one element
common mineral in pencils: Graphite C
Oxides - formula contains O (but no Si, C, S)
common mineral in rust: Hematite Fe2O3
Hydroxides - formula contains OH
also common in rust: Goethite FeO(OH)
Carbonates - formula contains CO3
most common, many shells: Calcite CaCO3
Sulfides - formula contains S
fool’s gold: Pyrite
FeS2
Sulfates - formula contains SO4
used for plaster: Gypsum
CaSO4•2H2O
Phosphates - formula contains PO4
common mineral in teeth: Apatite Ca5(PO4)3(OH)
Halides - formula contains Cl, F, I, or Br
table salt: Halite NaCl
Minerals
• naturally occurring, inorganic, crystalline solid
• ordered atomic arrangement
• definite chemical composition
2 minerals can have:
or
same composition but
different structures
ex., Graphite & Diamond (C)
same structure but
different compositions
rhodochrosite
MnCO3
Photo Copyright © 2007
Michael C. Roarke
calcite
CaCO3
http://images.tutorvista.com
siderite
FeCO3
BUT no 2 minerals have the same combination
Minerals
• naturally occurring, inorganic, crystalline solid
• ordered atomic arrangement
• definite chemical composition
give rise to
CHARACTERISTIC
PHYSICAL PROPERTIES
that are used to ID them
LUSTER
CLEAVAGE &
FRACTURE
HARDNESS
STREAK
SPECIAL
SPECIFIC GRAVITY
COLOR
Crystal Habit = Growth shape
Cleavage & Fracture = Breakage Style
Cleavage = Planar Breakage
ex. 1 direction
Fracture = NONPlanar Breakage
irregular = rough surfaces
ex. 3 directions at 90˚
hackly = pointy surfaces
conchoidal = curved surfaces
ex. 4 directions
Hardness = Resistance to Scratching
Mohs Hardness Scale
1
2
3
4
5
6
7
8
9
rather than having a
Fingernail = 2½
Penny = 3½
Glass = 5½
10
Rocks
Aggregates of
minerals
&
Minerals
• naturally occurring
• inorganic
• crystalline solid
= ordered atomic arrangement
• definite chemical composition
Aggregates of
elements
Quartz
SiO2
K-feldspar
KAlSi3O8
Hornblende
(Ca,Na)2-3 (Mg,Al,Fe)5Si6 (Si,Al)2O22(OH)2
3 Main Rock Types:
Igneous, Sedimentary, Metamorphic
http://explore.ecb.org
Igneous
Rocks & Minerals
Crystallize from a melt
Making Igneous Rocks…
~1400˚C
~700˚C
http://www.youtube.com/watch?v=3Qasw7lb2UM
Rocks with different compositions can be produced because
different minerals melt or crystallize at different temperatures
** BOWEN’S REACTION SERIES **
Making Different Igneous Rocks…
Different substances melt or crystallize at different temperatures
Composition
Cooling Temperature
Igneous Rock Classification is based on
Composition
and
Texture
Igneous “Texture”
Grain size
Cool quickly ⇒ no time to grow
Cool near/at surface
“Aphanitic”
“not seen”
Cool slowly ⇒ time to grow
Cool deep ⇒ insulated
http://www.windows2universe.org/
Texture
Cooling Rate
“Phaneritic”
“seen”
Igneous Rock Classification is based on
Composition
and
Texture
"Igneous" Minerals
Minerals from Bowen's Series
Cleavage & Fracture = Breakage Style
Cleavage = Planar Breakage
ex. 1 direction
Fracture = NONPlanar Breakage
irregular = rough surfaces
ex. 3 directions at 90˚
hackly = pointy surfaces
conchoidal = curved surfaces
ex. 4 directions
Igneous Rock Classification is based on
Composition
and
Texture
Most abundant in Earth's crust:
O
Si
Al
Fe
Ca
Na
K
Mg
74.3%
8.2%
Silicates ~92%
12% Quartz
GRANITE
36.9%
12% K-feldspar
40% plagioclase feldspar
17.5%
11% pyroxene
BASALT
42.5%
Making Different Igneous Rocks…
Different substances melt or crystallize at different temperatures
Two Processes differentiate rocks:
1. Partial Melting
Different substances melt at different temperatures
Two Processes differentiate rocks:
1. Partial Melting
chocolate chips
vanilla ice cream
Starting
with solid
Oceanic Crust is made of BASALT
Silly Putty-like solid
Ultramafic composition
Oceanic Crust is made of BASALT
Two Processes differentiate rocks:
2. Fractional Crystallization
Starting
with melt
chocolate chips
vanilla ice cream
Two Processes differentiate rocks:
1. Fractional Crystallization
Crystallization Order
chocolate chips
vanilla ice cream
periods of crystallization over time
Continental Crust is mostly made of GRANITE
thicker
Continental crust is
and
than oceanic crust
magma stalls longer below continental crust.
undergoes more fractional crystallization
Different minerals melt & crystallize
at different temperatures
Chocolate chips ⇔ dark, mafic minerals
Vanilla ice cream ⇔ light, felsic minerals
Most abundant in Earth's crust:
92% = igneous & metamorphic rocks
GRANITE
36.9%
BASALT
42.5%
8% = sedimentary rocks
SHALE
50%
CARBONATES
25%
SANDSTONES
25%
BUT... 95% of surface rocks are
SEDIMENTARY
Sedimentary
Rocks & Minerals
Made of sediment:
crushed up bits
(clasts)
dissolved bits
(ions in solution)
Sediments are materials weathered from pre-existing rocks
Weathering
Erosion
http://www.learner.org/interactiv
es/rockcycle/diagram.html
Transport
Deposition
Burial
Compaction
Cementation
Harden into rock
http://www.learner.org/interactives/rockcycle/diagram.html
LITHIFICATION
4 WAYS TO TRANSPORT SEDIMENT:
WIND
and
WATER
Typically:
~ Well Sorted
Rounded
Layered
GRAVITY
and
GLACIERS
Typically:
UNsorted
UNrounded
UNlayered
Sorting – Waterlain Deposits
Very well sorted
Not so well sorted
Reworked
http://www.maine.gov/doc/nrimc/mgs/explore/bedrock/fact
s/nov06-5.htm
Deposited without reworking
CLASTIC SEDIMENTS in CLASTIC ROCKS
Grains become more
rounded during
transport
angular edges break off as
grains bounce and roll along
http://www.youtube.com/watch?NR=1&v=O9GVRKnMch8&feature=endscreen
CLASTIC SEDIMENTS in CLASTIC ROCKS
Grain sizes that get
deposited become
smaller with distance
from source.
Competence:
maximum grain size
that can be carried
controlled by energy of flow
controlled by slope
slope decreases downstream
CLASTIC SEDIMENTS in CLASTIC ROCKS
Weak minerals disintegrate so
only strong minerals remain
Minerals low on Bowen’s Series
• form at temperatures that are closer
to those at Earth’s surface, so they
are more stable on the surface than
minerals formed at higher temperatures
• are more silica-rich, resulting in structures in
which the silica bonds together in strong frameworks.
Weathering Products
ex., rust (hematite), clays
Sedimentary Rocks
2 General Types
Terrigenous Clastic
from land
broken bits
Biochemical
precipitated from
dissolved ions
often with the
help of organisms
crushed up bits
(clasts)
+
dissolved bits
(ions in solution)
cement
dissolved bits
(ions in solution)
COMMON TERRIGENOUS CLASTIC ROCKS
• grain size decreases
• rounding increases
• weak minerals disintegrate
Increasing distance from source
COMMON TERRIGENOUS CLASTIC ROCKS
BIOCHEMICAL MINERALS
(precipitated from dissolved ions)
CALCITE
(CaCO3)
commonly: associated with marine settings
secreted as shells or feces
EVAPORITES
micoorganisms: forams, coccolithophores
HALITE
(NaCl)
typically : form in shallow basins with periodic
influxes of seawater followed by
evaporation of water, leaving
GYPSUM
(CaSO4•2H2O)
CHERT
(SiO2)
solids behind
commonly: precipitated by sponges and
micoorganisms: diatoms, radiolaria
or directly from seawater
http://www.youtube.com/watch?v=QwiPplYoH7Q&feature=related
BIOCHEMICAL ROCKS
CALCITE
EVAPORITES
(CaCO3)
HALITE
(NaCl)
GYPSUM
(CaSO4•2H2O)
LIMESTONE
ROCK SALT
ROCK GYPSUM
CHERT
(SiO2)
How would you test for limestone?
Metamorphic
Rocks & Minerals
"Meta" = change
"Morph" = form
METAMORPHISM OCCURS IN
3 DIFFERENT WAYS:
1.) RECRYSTALLIZATION:
Crystals grow larger
2.) FOLIATION: preferential alignment of crystals,
metamorphic layering
3.) NEOMORPHISM: existing minerals become
unstable and are reconfigured as new minerals,
such as garnet, kyanite or sillimanite.
http://www.youtube.com/watch?v=bxpOBVAcMHI&feature=related
Metamorphism occurs through
increased temperature &/or pressure
THERE ARE TWO MAIN
TYPES OF METAMORPHISM
CONTACT
METAMORPHISM from
Subduction zones & ContinentContinent Convergent Boundaries are
increased temperatures occurs
around any magma chamber
areas of REGIONAL
METAMORPHISM
METAMORPHIC ROCK TYPES THAT CONTAIN PLATY
MINERALS ARE DISTINGUISHED BY THEIR FOLIATION:
"Before" "Rock"
PROTOLITH
SHALE
QUARTZ
SANDSTONE
LIMESTONE
3 Main Rock Types:
Igneous, Sedimentary, Metamorphic
The
Rock Cycle
& Tectonics
http://eo.ucar.edu/kids/green/cycles8.htm
3 Main Rock Types:
Igneous
• interlocking crystals
• no layers
Metamorphic
• interlocking crystals
• layers
Sedimentary
• cemented grains (gritty feel common)
• layers
• may contain fossils
Rocks as seen through a microscope
(plane light)
(x-polars)
MELTING A ROCK
1. CHANGES IN TEMPERATURE
OR PRESSURE
2. ADDITION OF WATER
(from dewatering of minerals)
LIQUID
Low pressure
favors the
less dense state
Pressure
pushes atoms
together
X
X
High pressure
favors the
more dense state
SOLID
Heat = Energy
Energy excites atoms so
pushes atoms apart
High temperature
favors the
less dense state
LIQUID
Water lowers the
melting temperature of
minerals & rocks