Transcript Understanding Our Environment

Geology and Earth Resources
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Outline
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Basic Stats
Geologic Time
Tectonic Processes
Rocks and Minerals
 Rock Cycle
Economic Geology and Mineralogy
Environmental Effects of Resource Extraction
 Mining
- Reclamation
Conserving Geologic Resources
Geologic Hazards
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Basic Earth Statistics
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Orbit
Diameter
Mass
How did we get the
name Earth?
Go to
http://www.nineplanets.
org/earth.html to help
you!
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Just How Old is the Earth?
Start with the activity Geologic Time Scale to
a. determine number of years between the various
eons and periods
b. Review the fossil record
c. Create a “calendar” for geologic time.
d.
Go to
http://www.paleobio.org/education/timescale.html
to view the timescale presented by PaleoBio.org
e. Watch the video segment on the geologic calender
from “Cosmos” (ask Ms. P!)
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Do you remember when…?
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Go to
http://www.windows.ucar.edu/tour/link=/earth/
interior/earths_crust.html&edu=high AND
http://earthnetgeonet.ca/teachers/PlanetEarthMar04.pdf
PDF page 63 (article page 59)
Create a “concept map” based on the
eras/periods and the important occurences
in each era or period.
Use the info on the next slide to help you!
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Concept Mapping
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Great idea for complex concepts!
Helps you to remember information better!
VERY helpful for APES!
http://www.smartdraw.com/specials/mindmap
ping.asp?type=13054&id=13054 – download
to your computer and get mapping – at
HOME!
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ONE MORE TIME!
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Let’s “rock around the clock” by looking at yet
ANOTHER way to see the relationship
between geologic time and important events
in the evolution of organisms on earth. Go to
http://earthnetgeonet.ca/teachers/PlanetEarthMar04.pdf
PDF page 64 (article page 60)
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Closure Question
In the 4 billion plus years of the Earth’s
existence, there have been periodic “blooms”
of life, often following massive extinctions.
Name these periods of earths history ( within
eras) and state what life “bloomed” during
each period.
If extinction is typical and natural for Earth’s
history, why then is there so much concern
for the rapid disappearance ( up to 1
species/day) the Earth currently
experiences?
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It’s a little hot in here, isn’t it?
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A DYNAMIC PLANET
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A Layered Sphere
 Core - Interior composed of dense, intensely hot
metal. Generates magnetic field enveloping the
earth.
 Mantle - Hot, pliable layer surrounding the core.
Less dense than core.
 Crust - Cool, lightweight, brittle outermost layer.
Floats on top of mantle.
 Go to
http://www.seed.slb.com/en/scictr/watch/living_pl
anet/beneath.htm for more info, especially on
core and mantle convection effects on plate
tectonics.
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Earth’s Cross Section
What are the depths of the
various layers of earth?
http://www.nineplanets.org/
earth.html
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http://www.evergreen.edu/
washcenter/modules/stude
nt_versions/S-1-3BShells_2.ppt#257,1,Slide1
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What is the function of the
Mohorovicic boundary?
http://www.nineplanets.org/
earth.html
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How do the lithosphere and
athenosphere differ?
http://www.windows.ucar.edu/t
our/link=/earth/interior/earth
s_crust.html&edu=high
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What elements make up the different layers of
the Earth?
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At right is a breakdown
of some of the
materials the earth is
made up of. For more
info, go to
http://www.nineplanets.
org/earth.html
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Closure Question
Name the layers of the earth in cross section.
Where is the location of the lithosphere,
asthenosphere and the Milhorovicic
discontinuity?
Explain the organization of the planet in cross
section using a simple property discussed in
several webpages you viewed yesterday.
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Tectonics
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Tectonic Processes
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Upper layer of mantle contains convection
currents that break overlaying crust into a
mosaic of tectonic plates.
 Slide slowly across earth’s surface.
- Ocean basins form where continents
crack and pull apart.
- Magma forced up through cracks in
oceanic crust form mid-oceanic ridges.
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What forces are behind Plate Tectonics?
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Go to
http://www.ucmp.berkeley.edu/geology/tecme
ch.html and take notes on
Mid-ocean ridges
Geomagnetic anomalies
Deep Sea Trenches
Island Arcs
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Activity!
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Investigation 2 Plate Tectonics
Plot key geologic events and correlate them to
tectonic plate boundaries!
Also look at
http://www.ucmp.berkeley.edu/geology/anim1.html
for help. This animation runs fast! To help you,
also open
http://kids.earth.nasa.gov/archive/pangaea/conclusi
on.html for the same animation that can be
controlled by you.
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Pangea
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Geologists suggest that
several times in earth’s
history most, or all, of
the continents gathered
to form a single supercontinent, Pangea,
surrounded by a single
global ocean. This was
only possible because
of Plate Tectonics
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What will Earth look like in the future?
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Go to
http://kids.earth.nasa.gov/archive/pangaea/c
onclusion.html and write down the expected
changes that should occur over the next
several million years!
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Earthquake!
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Tectonic Processes Cause Earthquakes
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Earthquakes are caused by grinding and
jerking as plates slide past each other.
 Mountain ranges pushed up at the margins
of colliding plates.
- When an oceanic plate collides with a
continental landmass, the continental
plate will ride up over the seafloor and
the oceanic plate will subduct down into
the mantle.
 Deep ocean trenches mark
subduction zones.
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Demo folding and faulting!
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Take the bag of cornstarch and water and
POUR it into a clean petri dish
Using your fingers, experiment with the
mixture.
 What happens if you push the mixture very
fast or hard? Gently push? Slowly push?
 Relate this to the movement of particles of
soil/rock as folding or faulting occurs over
geologic time.
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Know Your Plate Boundaries!
Go to
http://www.seed.slb.com/en/scictr/watch/living_planet/mount
ains.htm and click on any picture to see the animation of all
four types.
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Tectonic Plate Movement
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Mid-Atlantic Ridge Plate
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Is the best studied
plate of all
Iceland and Surtsey
Island are both formed
from the Mid-Atlantic
Ridge Plate
Are evidence of
divergent plate action
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Divergent Plate Action
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Divergent Plate Action and Formation of Magnetic
Zones in the crust
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Thingvellir fissure zone is
a ground level portion
of the Mid-Atlantic
Ridge
Active volcanoes are
frequent on Iceland
and Surtsey Island
along the fissures
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Check it Out!
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Go to
http://www.classzone.com/books/earth_scien
ce/terc/content/visualizations/es0808/es0808
page01.cfm?chapter_no=visualization to see
how a subduction zone boundary plate will
cause continent building between two
exposed plates.
This is the way the Himalayan Mountain
Range was formed from the subduction of
the Indian-Australian plate to the Eurasian
plate.
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GEOLOGIC HAZARDS
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Earthquakes - Sudden movements of the
earth’s crust that occur along faults where
one rock mass slides past another.
 Gradual movement - creep.
- When friction prevents creep, stress
builds up until eventually released with a
sudden jerk.
 Frequently occur along subduction
zones.
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I fell in to a burning ring of fire…
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Go to
http://www.seed.slb.com/en/scictr/watch/livin
g_planet/beneath.htm to learn more about
the Pacific Rim’s “Ring of Fire”
What problems are seen in this region that
are not seen in the Atlantic Rim?
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Epi-wha?
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Earthquake Epicenters
Go to
http://www.seed.slb.com/en/scictr/watch/livin
g_planet/ringoffire.htm and click on
“Earthquake Epicenters” at the bottom for the
animation.
Where are the majority of epicenters
located?
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It’s the Mud?
Go to
http://www.nationalacademies.org/headlines/
20060215.html and read about how
sediments in subduction zones may help
trigger earthquakes.
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TSUNAMI!!!
Or Seismic sea swells.
How do they form?
How are they different from wind-driven ocean
waves?
Go to
http://esminfo.prenhall.com/science/geoanim
ations/animations/86_Tsunami.html and to
http://www.seed.slb.com/en/scictr/watch/livin
g_planet/tsunami.htm
Click on the animation in the second website to
see a tsunami from earthquake to land fall.
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Not all earthquakes create tsunamis
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Why is this? To answer, go to
http://www.seed.slb.com/en/scictr/watch/livin
g_planet/why_no_tsunami.htm and find out
what it takes to make an earthquake-driven
tsumani form.
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Charles Richter and his scale
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Charles Richter developed a logarithmic scale by
which to determine earthquake magnitude.
Go to
http://library.thinkquest.org/C003603/sims/earthqua
kes/ie.html# and follow the directions to see how
earthquake shaking changes as magnitude
increases.
Then go to
http://www.seismo.unr.edu/ftp/pub/louie/class/100/
magnitude.html and see the effects of an
earthquake based on it’s Richter magnitude
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Seismicity and Seismographs
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Developed by Richter in 1935
Measures seismic activity and records onto paper as the
paper is rolled out
Check out Seismograph history by going to
http://www.thetech.org/exhibits/online/quakes/seismo/
Shake yer booty! Compare and contrast seismicity by going
to
http://earthquake.usgs.gov/regional/states/seismicity/us_sei
smicity.php and comparing the East and West Coasts of the
Lower 48 states.
Now look at
http://earthquake.usgs.gov/regional/world/seismicity/index.p
hp for the world.
 What do the areas encircled by active seismic areas
represent? (Think Johnny Cash song)
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Volcanoes
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Volcanoes and undersea magma vents are
the sources of most of the earth’s crust.
 Many of world’s fertile soils are weathered
volcanic material.
- Human / Environmental Dangers
 Volcanic Ash
 Mudslides
 Sulfur Emissions
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Volcanoes
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Go to http://highered.mcgrawhill.com/sites/0072439564/student_view0/ch
apter14/web_exercises.html and complete
the activity!
NOTE – the link for the active volcanoes in
the Lower 48 states doesn’t work. Go to
http://www.nationalatlas.gov/dynamic/dyn_vo
l-us.html to see the interactive map!
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Type Me!
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There are three different types of active volcanoes! Go to
each website to view how these volcanoes form. Take or
review notes.
Rift volcanoes - Which island nation and it’s tiny neighbor
island was formed from a Mid-Atlantic Rift volcano?
http://www.classzone.com/books/earth_science/terc/content/
visualizations/es0903/es0903page01.cfm?chapter_no=visu
alization
Subduction volcanoes – Which famous volcano on the West
Coast is formed by subduction? It’s making noises again!
http://www.classzone.com/books/earth_science/terc/content/
visualizations/es0902/es0902page01.cfm?chapter_no=visu
alization
Hot Spot Volcanoes – Which chain of islands was formed by
hot spot volcanoes?
http://www.wwnorton.com/earth/egeo/animations/ch2.htm
and scroll down to 2.11
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Peeee Uw!
Volcanoes give off gases when they erupt,
along with the lava, etc. Go to
http://pubs.usgs.gov/of/1997/of97-262/of97262.html to determine the climatic
implications of major volcanic eruptions.
• Go to
http://volcano.und.edu/vwdocs/Gases/averag
e.html and make sure you know the types of
major and minor gases given off by
volcanoes
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Destruction!
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Go to
http://www.pbs.org/wnet/savageearth/hellscr
ust/html/ind-vid.html and watch how a town is
destroyed by volcanic lava flows.
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DVD –Forces of Nature
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Pop the DVD into the computer and watch
the segment on “Island of Fire” and “A Living
Lab” (Scenes 2 & 3)
Take/review notes as you watch.
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Let’s Rock!
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ROCKS AND MINERALS
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A mineral is a naturally occurring, inorganic,
solid element or compound with a definite
chemical composition and regular internal
crystal structure.
A rock is a solid, cohesive, aggregate of one
or more minerals.
 Each rock has a characteristic mixture of
minerals, grain sizes, and ways in which
the grains are held together.
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Rock Types
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Rock Cycle - Cycle of creation, destruction, and
metamorphosis.
 Three major rock classifications:
- Igneous
- Sedimentary
- Metamorphic
- Go to
http://www.classzone.com/books/earth_scienc
e/terc/content/investigations/es0602/es0602pa
ge02.cfm to see the rock cycle in action!
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Rock Cycle
Create your own concept map to help you remember!
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Igneous Rocks
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Most common type of rock in earth’s crust.
 Solidified from magma extruded onto the
surface from volcanic vents.
- Quick cooling of magma produces finegrained rocks.
 Basalt
- Slow cooling of magma produces
coarse-grained rocks.
 Granite
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Sedimentary Rock
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Deposited materials that remain in place long
enough, or are covered with enough material for
compaction, may again become rock.
Go to www.classzone.com/books/earth_science/
terc/navigation/visualization.cfm (open Explorer
and copy/paste address) and watch Chapter 6
animation on the formation of sedimentary rock
 Formed from crystals that precipitate out of, or
grow from, a solution.
- Shale
- Sandstone
- Tuff
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Striated Sandstone Sits Sweetly
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How do those stripes get into sandstone? To
find out, go to
http://www.seed.slb.com/en/scictr/watch/strat
ifi/index.htm to answer this question!
Read more on an experiment that shows
how this occurs and do the experiment
virtually! Go to
http://www.seed.slb.com/en/scictr/watch/strat
ifi/stratifi.htm and git er done!
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How Geologists “Read” Sedimentary Layers
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Go to http://earthnetgeonet.ca/teachers/PlanetEarthMar04.pdf
PDF page 59 (article page 55) to see how
sediment layers form AND how fossils are
formed.
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Metamorphic Rock
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Pre-existing rocks modified by heat, pressure, and
chemical agents.
 Chemical reactions can alter both the
composition and structure of rocks as they are
metamorphosed.
 Go to www.classzone.com/books/earth_science/
terc/navigation/visualization.cfm , Chapter 6 and
watch the animation for Metamorphic rock
formation.
- Marble (from limestone)
- Quartzite (from sandstone)
- Slate (from mudstone and shale)
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Experiment!
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Click on
http://www.seed.slb.com/en/scictr/watch/stratifi/stratifi.htm.
Then click on “Digging Deeper” from the bottom box.
In the pop-up box, scroll down and click on “Porosity” and
run the experiment. Make sure to use your lab book to fill in
tables and answer questions.
 Make sure to calculate the information requested!
Go back and click on “The Absorbency of Rock” and run the
experiment. Ditto on using lab book and calculations.
All lab materials are located on the cart.
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Rock Cycle and Weathering
For an in depth explanation of the Rock Cycle
and Weathering go to:
http://gpc.edu/~pgore/geology/geo101/weather.
htm
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Weathering and Sedimentation
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Mechanical - Physical break-up of rocks into smaller
particles without a change in chemical composition.
Chemical - Selective removal or alteration of specific
components that leads to weakening and disintegration of
rock.
 Oxidation
Sedimentation - Deposition of loosened material.
Go to
http://courses.soil.ncsu.edu/resources/soil_classification_ge
nesis/mineral_weathering/mineral_weathering.swf
and
http://courses.soil.ncsu.edu/resources/soil_classification_ge
nesis/mineral_weathering/elemental_change.swf to see how
weathering occurs and factors that facilitate different types
of weathering.
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Mass Wasting
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Occurs when materials are moved
downslope from one place to
another.
 Many human activities such as
forest clearing and building
homes on unstable slopes
increase both frequency and
damage done by landslides.
 Can also occur when rains cause
mass erosion of soils
 For more, go to
http://gpc.edu/~pgore/geology/ge
o101/masswasting.html
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Rocky Road
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Complete the laboratory handout “The Rock
Cycle, Rocks and Soil”
Use the materials on the cart.
Make sure to place this lab in your lab book
when you are done.
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ECONOMIC GEOLOGY AND MINERALOGY
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Metals
 Metals consumed in greatest quantity by
world industry (metric tons annually):
- Iron
(740 million)
- Aluminum
(40 million)
- Manganese
(22.4 million)
- Copper and Chromium (8 million ea)
- Nickel
(0.7 million)
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Non-Metal Mineral Resources
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Sand and Gravel
 Brick and concrete construction, paving,
sandblasting and glass production.
Limestone
 Concrete and building stone
Evaporites
 Gypsum and Potash
Sulfur
 Sulfuric Acid
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ENVIRONMENTAL EFFECTS OF
RESOURCE EXTRACTION
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Mining
 Placer Mining - Hydraulically washing out
metals deposited in streambed gravel.
- Destroys streambeds and fills water with
suspended solids.
- Research – What other problems does
this cause in the streams? Go to
http://eesc.orst.edu/salmon/human/minin
g.html for more info.
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ENVIRONMENTAL EFFECTS OF RESOURCE
EXTRACTION
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Strip-Mining or Open Pit Mining
- Large scars on land surface.
- Tailings
 Toxic runoff – go to
http://geology.er.usgs.gov/eastern/env
ironment/drainage.html and take
notes/look at photos of acid mine
drainage
 Also
http://www.hcn.org/servlets/hcn.Article
?article_id=1233 for lead/zinc mines
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Mining
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Underground Mining
Three types of underground mines – go to
http://www.umwa.org/mining/ugtype.shtml and
http://66.113.204.26/mining/coal/undergnd_mining.htm and take notes
(you may also download the pics if needed)
 Extremely Dangerous
- Gas
- Inhaling Particulate Matter
- Tunnel Collapse
- Go to
http://www.npr.org/templates/story/story.php?storyId=5125860
and take notes on problems and solutions in coal mining.
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Also go to http://www.pbs.org/newshour/bb/health/janjune06/minetown_2-01.html and take notes on some of the worst
of the mining disasters.
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Be a Miner!!
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Pretend you are a miner. Your job is to remove the “precious chunks of
chocolate” without removing any more surrounding “soil” then
necessary.
Use the handout “Cookie Mining” for the directions on how to run the
lab.
All materials are located on the lab cart. And yes, you may eat ONE
cookie.
Use the lab activity sheets located in the APES Private folder, Earth
Systems and Resources. to record your info and answer lab questions.
When the class is finished, open the MS Excel spreadsheet in the APES
private folder and enter the class data on it. Once everyone has done
this, run off a copy for you to use per lab directions.
Make sure to wash the tools with soap and water before using
(meoooow!)
All papers must go in your lab notebook!
Don’t forget your Internet research!!!!
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Copper Extraction Lab
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Okay, we’ve played at mining with cookies;
now let’s really mine something important!
Copper is an essential component for many
different products, so essential that
processing copper from old mine tailings has
become a very profitable business.
Conduct the lab using the materials given
Remember to consider all safety precautions!
Answer the questions when finished!
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Wasteful Mining
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“Dirty gold” is a problem in gold ore mining.
Read the following to understand what all the
noise is about.
http://www.msnbc.msn.com/id/4607954/
http://www.professionaljeweler.com/archives/
news/2004/022304story.html
Just how much dirt is moved to make one
18K gold ring? Is it worth it?
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Health and Mining
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Describe how “black lung disease” is caused
by working in or on a coal mine.
http://www.msha.gov/S&HINFO/BLUNG/HO
MEPAGE.HTM
For pictures, go to
http://www.umwa.org/blacklung/intro.shtml
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Restoration – know this law!!!
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Surface Mining Control and Reclamation Act
(1977) requires better restoration of stripmined lands, especially if land is classed as
prime farmland.
 Difficult and expensive.
- Minimum reclamation costs about
$1,000 / acre while complete restoration
may cost $5,000 / acre.
 50% of U.S. coal is strip mined.
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Land Reclamation
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For more information, go to
http://www.mii.org/coal/coal.html
http://www.arippa.org/landreclamation.asp
If you had land that could be strip mined for
coal, would you allow it? Here is one man’s
story.
http://www.neighborsforneighbors.com/Media
Pages/AAS/Russell%20Bostic/15elgin.html
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Processing
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Metals are extracted from ores by heating or
treatment with chemical solvents.
 Smelting - Roasting ore to release metals.
- Major source of air pollution. Go to
http://www.ec.gc.ca/cleanairairpur/Base_Metals_Smelting-WSB06262AE1_En.htm for a list of pollutants released.
 Heap-Leach Extraction - Crushed ore piled in
large heaps and sprayed with a dilute alkaline
cyanide solution which percolates through the
pile to dissolve the gold.
- Effluent left behind in ponds.
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Heap Leaching Kills!
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Go to
http://journalism.uts.edu.au/miningoz_2004/D
irtyGold/ and take notes on the ecological
disasters that are occurring due to Heap
Leached gold.
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CONSERVING GEOLOGIC RESOURCES
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Recycling
 Aluminum must be extracted from bauxite
by electrolysis.
- Recycling waste aluminum consumes
one-twentieth the energy of extraction
from raw ore.
 Nearly two-thirds of all aluminum
beverage cans in U.S. are recycled.
 Other metals commonly recycled:
- Platinum, gold, copper, lead, iron, steel.
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Substituting New Materials For Old
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Reduce metal consumption by using new
materials or new technologies.
 Plastic pipes in place of metal pipes.
 Fiber-optics in place of metal wires.
 Metal alloys in place of traditional steel.
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What’s an Alloy?
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Metal Alloys contain more than one metallic
element. Their properties can be changed by
changing the elements present in the alloy.
Examples of metal alloys include stainless
steel which is an alloy of iron, nickel, and
chromium; and gold jewelry which usually
contains an alloy of gold and nickel.
http://www.mse.cornell.edu/courses/engri111/metal.htm
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Seasons and Djibouti
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After completing the Seasons handout, go
tohttp://www.teachersdomain.org/912/sci/ess/watcyc/naturalchange/index.html
to see how a change in the earth’s axis,
declination and procession can change the
climate!
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Summary
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Tectonic Processes
Rocks and Minerals
Economic Geology and Mineralogy
 Strategic Resources
Environmental Effects of Resource Extraction
 Mining
- Reclamation
Conserving Geologic Resources
Geologic Hazards
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