Download Volcano Lab 16-17 File

Engel’s Science on a shoestring © Simonized
SCORIA CONE
Volcanoes at Destructive Boundaries:
1. Plates move together or apart because of convection
. currents
2. Heavier (Denser) oceanic plate is sub-ducted.
3. Friction between the plates and heat from the interior
causes the subducting plate to melt.
4. Melting of the plate creates molten magma.
5. This magma is less dense than its surrounding rock and
is erupted at the surface through a weakness in the crust,
creating a volcano.
6. Volcanoes at convergent boundaries tend to be explosive
due to the build up of pressure and gases.
Straight sides with steep slopes; large
summit crater, about 1,000 ft
Basalt tephra; occasionally
andesitic
Strombolian
SHIELD VOLCANO
Very gentle slopes; convex upward
Basalt lava flows
Hawaiian- about 200-27,000ft
STRATOVOLCANO
5-15,000 ft
Highly variable; alternating
basaltic to rhyolitic lavas and
tephra andesite composition
variable; alternating basaltic to
rhyolitic lavas and tephra with
an overall andesite composition
Gentle lower slopes, but steep upper
slopes; concave upward; small summit
crater
Volcanoes at Constructive Boundaries:
1. Plates move away from each (divergent) other due to convection currents
2. This creates a weakness or a ‘gap’ in the crust.
3. Magma is able to rise to plug the gap forming lava flows and submarine
volcanoes.
4. As magma continues to build up above the surface of the ocean, volcanic
islands (such as Hawaii) may form.
5. Eruptions at constructive boundaries tend to be gentle with little pressure
build up.
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Open the following link and answer the questions that follow.
http://www.pbs.org/wnet/savageearth/animations/volcanoes/main.html
1. Under the volcano cone is the ___________ chamber that hold molten magma.
2. The explosive escape of the gases from the magma causes a violent
______________________.
3. Because the fragments of rock and ash are heavier than air and may not mix with
enough air to remain high aloft, they may surge down the sides of the volcano as
dangerous "__________________________flows."
Open the following link and answer the questions that follow.
http://www.pbs.org/wnet/savageearth/animations/index.html
4. A stratovolcano is made out of _____________ of ash and lava from previous
eruptions.
5. Magma is lighter or less dense than solid ________________.
6. Once magma reaches the surface it is called _________________.
Open the following links and answer the questions that follow.
http://www.classzone.com/books/earth_science/terc/content/investigations/es0810/es0810page01.cfm
7. Which island is made of at least three volcanoes? _______________
8.On which island is Pearl Harbor located? _________________
http://www.classzone.com/books/earth_science/terc/content/investigations/es0810/es0810page03.cfm
9. What is the Lithosphere floating on? _________________
10. Where are the extinct volcanoes found? ________________________
______________________________________________________________
11. Where are the active one(s) found? ________________________________
______________________________________________________________
http://www.classzone.com/books/earth_science/terc/content/investigations/es0810/es0810page07.cfm
12. Where is Yellowstone National Park located? _________________
13. What can you use as proof that there is a hotspot under Yellowstone?
___________________________________________________
Bonus
http://www.classzone.com/books/earth_science/terc/content/investigations/es0810/es0810page08.cfm
What is the rate of plate motion under Yellowstone for the last 600,000 years?
_________________
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Using dichotomous keys to determine the type
of rock (Go to the wet side of the lab now!)
Igneous rock was once melted and cooled to form a solid. The
faster the rock cools, the smaller the crystals in the rock. When
rock cools very inside the earth slowly we call it intrusive. The
crystals that form grow to large sizes like the granite in our lab
desk tops. When rocks cool quickly, near or even at the surface of
the earth we call it extrusive and the crystal size or grain is
sometimes so small as not to be visible to the human eye. Some
rocks that cool vary fast have no crystals structure at all. In some
cases as the rocks burst to the surface gasses expand under the
reduced pressure to form pockets of gas like Swiss cheese and reduce the density of the rock.
Rock
type
Crystal
size
Intrusive
Coarse
(Larger
than
sand
sized)
Extrusive
Fine
(smaller
than
sandsized)
Extrusive
Extrusive
Felsic
(Aluminum)
Low
Light colored
or red hued
Element Composition
Density
Color
Mafic
(Iron and Magnesium)
High
Dark-colored
or green hued
Granite
Gabbro
Rhyolite
Basalt
Obsidian (Nearly same chemical
makeup as Granite)
Obsidian is called natural or volcanic
glass because of atomic structure to glass.
Color-black, red brown or gray Fractures
curved structures.
Volcanic glass that has many holes, so
many sometimes it floats on water. Colorwhite, gray, grayish brown.
Pumice (Nearly same chemical
makeup as Granite)
Igneous rock can be put in categories based on their color and crystal size. Below is a data table that
lists some colors and crystal sizes.
Data Table
Crystal size
Color
Rock Name
Large
Generally pink
23.
Large
Black
24.
Smaller than sand sized
Blackish green
25.
Smaller than sand sized
Generally light colored
26.
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27. List two intrusive rocks _____________________ and ________________________
28. Did both of these types of rocks cool quickly or slowly? _____________________
29. How do you know? _____________________________________________________
30. Do all extrusive igneous rocks contain crystals? ___________________________________
_________________________________________________________________________
31. Give two in this lab that do not ____________________ and ______________________
32. Why do some igneous rocks have bubble holes? _______________________________
33. Give two extrusive igneous rock that contain crystals, ________________and
______________________
34. Obsidian and Granite have most of the same elements. How are they different?
______________________________________________________________________________
_____________________________________________________________________________
35. What is the name of the igneous rock that has a blackish green color and cooled deep below
the earth’s surface? ____________________________
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Volcanoes at Destructive Boundaries:
1. Plates move together or apart because of __________________ currents.
2. Heavier (______________) oceanic plates are ____________________.
3. _______________ between the plates and _______________ from the interior causes
the subducting plate to melt.
4. Melting of the plate creates ___________________ _____________________.
5. Magma is less dense than its surrounding rock and is erupted at the surface through a
weakness in the crust, creating a ______________________.
6. Volcanoes at convergent boundaries tend to be _________________ due to the build up
of ____________________________and __________________________.
Volcanoes at Constructive Boundaries:
1. Plates ________________________________________ (divergent) due to convection
currents.
2. This creates a weakness or a ‘____________’ in the crust.
3. ____________________ is able to rise to plug the gap forming lava flows and submarine
volcanoes.
4. As magma continues to build up above the surface of the ocean, __________________
islands (such as ___________________________________) may form.
5. Eruptions at constructive boundaries tend to be _________________________ with
little __________________________ build up.
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http://www.bbc.co.uk/sn/tvradio/programmes/supervolcano/flash/supervolcano.shtml
Click on this site and watch the seismograph- Go to Seismic Signals
Label all the continents- http://kids.earth.nasa.gov/archive/pangaea/Pangaea_game.html
http://www.geology.sdsu.edu/how_volcanoes_work/
http://www.volcanolive.com/volcanolive.html
http://volcano.wr.usgs.gov/vhpstatus.php
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