# Chapter 3 Copymaster: Test, Reviews, Answer Keys, Chapter Schedule

Chapter #3 Copymaster includes tests and answers for students and teachers on material covered in Chapter 3.

Select options on the right hand side to proceed.

# Baseball Game

## Materials:

• One die
• One baseball diamond transparency
• Four markers for the runners

## Instructions

Break your class into two teams.
Ask a student a question. If they answer correctly award them the base that they rolled with the die. (See rules below) If they answer incorrectly their team is out. One out per inning.

## Rules for the game

1. Shake the die
1. single
2. double
3. triple
4. home run
5. single
6. single

2. Ask the question-If they answer correctly award them the base that they rolled with the die. Place a marker on the base that they earned. If there is a runner on base ahead of them move the runner the same amount of bases as the batter. If they answer incorrectly their team is out. One out per inning.

3. Keep rolling and asking questions until a player answers incorrectly. When they answer incorrectly switch batting teams.

# Chapter 3 Review

Chapter 3 Review
Cones, Eruptions, and Pyroclasts

Name___________________

1. What is lava?

2. Name the two smallest particles of pyroclastic material.

3. Name the two largest particles of pyroclastic material.

4. What is a pyroclastic flow?

5. What is the difference between pahoehoe and aa lava flows?

6. What is the difference between high and low viscosity magma?

7. How does a lava tube form?

8. Name the two reasons that volcanic eruptions occur?

9-14. Draw the three volcanic cone shapes and label each.

15-16. What are the two most non-explosive eruption types?

17-18. What are the two most explosive eruption types?

19. What is a hot spot? Use the term mantle plume in your definition.

20. What is a caldera?

21. How does a caldera form?

Chapter 3 Review
Cones, Eruptions, and Pyroclasts

1. What is lava?
Lava is molten rock on the surface of the Earth.

2. Name the two smallest particles of pyroclastic material.
Dust is the smallest of the pyroclasts and ash is the second smallest.

3. Name the two largest particles of pyroclastic material.
Blocks are large, sharp edged pyroclasts. Bombs are large, smoothly shaped pyroclasts

4. What is a pyroclastic flow?
A twirling mixture of very hot ash, gases, and other pyroclastic materials that are heavier than air and flow down a volcano at high rates of speed. (700 degrees and 100 miles per hour)

5. What is the difference between pahoehoe and aa lava flows?
Aa lava flows are very rough and fragmented. They are blocky in their appearance. Aa usually flows at a high rate of speed and cools slowly.
Pahoehoe usually flows at a very slow rate of speed. It is smooth and ropey in appearance.

6. What is the difference between high and low viscosity magma?
High viscosity magma is very thick and pasty. It usually has a large amount of dissolved gas . It usually erupts violently.
Low Viscosity magma is thin and runny with little dissolved gas. It usually erupts with thin flows of lava very quietly.

7. How does a lava tube form?
A lava tube forms a tunnel when the surface of the lava flow cools and hardens, while the interior keeps flowing through, draining away , leaving the interior hollow.

8. Name the two reasons that volcanic eruptions occur?
Magma will rise to the surface of the Earth when it is less dense than the surrounding rock in the mantle. When the magma reaches the surface of the Earth the pressure difference between the gases in the magma and the surface pressures allows the magma to boil out.

9-14. Draw the three volcanic cone shapes and label each.

Shield Cone-

Cinder Cone-

Stratovolcano or composite cone-

15-16. What are the two most non-explosive eruption types?
Icelandic and Hawaiian eruptions are the least explosive and dangerous of the eruption types.

17-18. What are the two most explosiveeruption types?
Plinian is the most explosive and Pelean is the deadliest.
19. What is a hot spot? Use the term mantle plume in your definition.
A hot spot occurs near the crust where very hot solid rock rises through the mantle (a mantle plume) and forms magma near the surface of the Earth. Hot spots form volcanoes in both oceanic plates and continental plates.

20. What is a caldera?
A caldera is a bowl-shaped depression caused by a volcanic eruption in which the top of the volcano collapses.

21. How does a caldera form?
A caldera will form when a volcanic eruption depletes the magma chamber causing a void under the volcano's summit. The weight of the top of the volcano causes it to collapse. A bowl-like depression or hole forms there.

# Chapter 3 Student Vocabulary

Vocabulary
Chapter 3

Name____________________

1. Lava-

2. Pyroclasts (Pyroclastic Rock)-

3. Pahoehoe-

4. Aa-

5. Viscosity-

6. Tube-

7. Dust-

8. Ash-

9. Blocks-

10. Bombs-

11. Pyroclastic Flows-

12. Pumice-

13. Obsidian-

Lesson #8 Volcanic Cones and Eruptions

1. Three Volcanic Cone Shapes-
2. Eruption Types-

Leson #9 Hot Spots-Hawaii and Yellowstone

1. Hot Spot-

2. Mantle Plume-

3. Caldera-

# Chapter 3 Teacher Vocabulary

Vocabulary
Chapter 3

Name____________________

1. Lava
Molten rock on the surface of the Earth.

2. Pyroclasts (Pyroclastic Rock)-
Pyro is Greek for fire and clastic means rock. Put them together and it translates into "Rock broken by fire". Pyroclasts are formed from the eruption of a volcano. Pyroclasts range in size from very small pieces of dust to ash to lapilli to bombs and block.

3. Pahoehoe-
A Hawaiian term for lava that has a smooth and ropey surface. Pahoehoe forms when the flow is slow and cools slowly.

4. Aa-
A Hawaiian term for lava that is rough and fragmented.
Aa lava forms when the lava flow is faster and the outside cools quickly causing the outside to become rough and fragmented.

5. Viscosity-
The resistance of flow in a liquid. Lava/Magma that is thick and pasty is said to have a high viscosity. High viscosity magma can hold a large amount of gas. This lava/magma usually will erupt violently when the gas that is dissolved in the magma escapes rapidly. Lava/magma that is thin and runny is said to have a low viscosity. These lava/magma will usually not erupt very violently. These eruptions will produce large amounts of lava and little pyroclastic material.

6. Tube-
A tunnel formed when the surface of a lava flow cools and hardens, while the still molten and flowing interior drains away.
7. Dust-
The smallest of the pyroclasts. Dust from volcanic eruptions have been known to stay floating in the atmosphere for years.

8. Ash-
Pyroclasts that are larger than dust. Very fine particles of exploded rock that can drift in the atmosphere for days.

9. Blocks-
Angular pieces of pyroclastic rock that is exploded from a volcano during an eruption.

10. Bombs-
Rounded pieces of pyroclastic material that are exploded during an eruption. These pyroclasts are in semi-plastic state and take their shape as they fly through the air.

11. Pyroclastic Flows-
Very hot turbulent gases, ash, and pyroclasts that are heavier than air and will flow down the side of a mountain at high speeds. These flows have killed thousands of people in some famous eruptions such as Vesuvius in 79 A.D., and Pele on the island of Martinique in 1902.

12. Pumice-
Pyroclastic rock that is in a semi-plastic state as it is shot through the air. The rock is full of gases that escape as the rock hardens. This rock is so full of holes that it floats on water.

13. Obsidian-
Lava rock that hardens very quickly. It can cool when it hits water or flowing down the side of a mountain. This rock is natures glass. It usually is dark green to black in color. Native peoples throughout the world have used it to make arrowheads, spears, and knives. It can be chipped to a very sharp edge.

Lesson #8 Volcanic Cones and Eruptions

1. Three Volcanic Cone Shapes-
• Cinder Cone-
Formed from eruptions of pumice and cinders. These cones rarely become more than 1000 feet tall. They are formed from very violent eruptions and can produce large amounts of dangerous gases.

• Shield Cone-
The largest of the cone types. These cones are formed from many eruptions of runny lava through the main vent and also through fissures on the flanks of the mountain. The largest volcano in the world, Mauna Loa, is a shield cone along with the rest of the Hawaiian Islands.

• Stratovolcano-
The most dangerous and beautiful of the volcanic cones. It is produced from the alternating eruptions of ash and lava. Some of the most famous volcanoes in the world are stratovolcanoes. Mt. Fujiama in Japan, Mt. Ranier and Mt. St. Helens in Washington, Mt. Etna in Sicily, and Mt. Vesuvius in Italy are all stratovolcanoes.

2. Eruption Types-
• Icelandic-
These eruptions are produced from many long cracks in the Earth called fissures. They are sometimes called flood eruptions because of the amount of lava produced. The magma is thin and runny and pours out of these fissures in great quantities. The great Columbian Plateau of Washington and Idaho were produced from Icelandic Eruptions. The lava that cover the Columbia Plateau is over a mile thick in places. They usually form shield cones.

• Hawaiian-
Very similar to Icelandic eruptions, the difference lies in the fact that the majority of the lava flows from the main vent in Hawaiian eruptions instead of through fissures. The lava is thin and runny and the eruptions are usually not violent. They usually form shield cones.

• Strombolian
Strombolian eruptions are short lived explosive eruptions that shoot very thick and pasty lava into the air along with bursts of steam and gas. These eruptions usually produce cinder cones.

• Vulcanian-
Vulcanian eruptions are more violent and explosive than strombolian eruptions. Vulcanian eruptions contain high dark clouds of steam, ash, and gas. The ash plume builds a cauliflower shaped head and a thinner more treetrunk-like base. When the volcano quits erupting ash and gases it then ejects thick pasty lava. Vulcanian eruptions usually build a steep sided cone that is more symmetrical than a cinder cone called stratovolcanoes (composite cones)

• Pelean-
Pelean eruptions are named for the catastrophic eruption on the island of Martinique in the Caribbean Sea in 1902. The eruption and the pyroclastic flow that followed killed 29,000 people almost instantly. "Glowing clouds" of gas and ash flew down the mountain at over 70 miles per hour. The cloud was so full of ash that it was heavier than air and hugged the ground as it approached the coast. The temperatures were probably around 700 degrees F. which would annihilate everything in its path.

• Plinian-
A Plinian eruption is the most explosive of the eruption types. Mt. St. Helens eruption was a plinian eruption. Plinian eruptions are characterized by a very high ash cloud that rise upwards to 50,000 feet (almost 10 miles) high. Very deadly pyroclastic flows are also part of plinian eruptions.
Mt. Vesuvius, which erupted in 79 A.D. in Italy, was a classic Plinian eruption. Very hot ash falls killed thousands of people in the city of Pompeii. Ash falls as high as 17 feet buried the city. Plinian eruptions were named for Pliny the Elder of Rome who died in one of the many eruptions of Vesuvius.

Lesson #9 Hot Spots-Hawaii and Yellowstone

1. Hot Spot-
A hot spot occurs because of the intense heat of the outer core. This heat radiates through the mantle bringing hot solid rock upward to the hot spot. These areas of rising solid rock are called mantle plumes. Hot spots do not move, but the plates above the hot spot moves producing island chains and the spreading of the oceans at mid-ocean ridges.

2. Mantle Plume-
Mantle plumes are areas of hot solid rising rock. This rock moves from the lower reaches of the mantle to the surface of the Earth causing the formation of volcanoes.

3. Caldera-
A caldera is a large bowl-shaped crater that is formed by the collapse of a volcanic cone after an eruption.

# Chapter 3 Test

Chapter 3 Test
Cones, Eruptions, and Pyroclasts

Name______________________

MATCHING

 1. ___Lava A. Rough and fragmented lava flows 2. ___Pahoehoe B. The most explosive eruption type. Ash plumes may reach 50,000 feet. 3. ___Plinian C. Molten rock on the surface of the Earth 4. ___Hawaiian D. Large pyroclasts-over 2 inches long with a rounded shape 5. ___Aa E. Smooth and ropey lava flows 6. ___Low Viscosity F. Thin and runny magma that usually erupts quietly with large amounts of lava. 7. ___Bombs G. Eruption type in which thin and runny magma reaches the surface of the Earth through the main vent and fissures.

8-9. Name two reasons that volcanic eruptions occur.

10-15. Name and draw the three kinds of volcanic cones.

16. What is a hot spot?

Fill in the blank with the correct answer. Use the following words to complete the blanks. Dust, Lava Tube, Mantle Plume, Ash, Caldera, Pyroclastic Flow, Blocks.

17. A large rough edged, angular pyroclast that is ejected during a volcanic eruption is called a _______________________.

18. A______________________ is a bowl-shaped depression caused by a volcanic eruption in which the top of the volcano collapses.

19. The smallest of the pyroclasts are called ___________________. They may stay in the atmosphere for years.

20. A ____________________ forms when the surface of the lava cools and hardens, while the molten interior flows through and drains away.

21. __________________ is the second smallest pyroclast. This material along with lava builds stratovolcanoes larger with repeated eruptions.

22. A ____________________ is very hot, solid rock that rises through the mantle and will become magma as it reaches the surface of the Earth. They form hot spots.

23. A_________________________ is a very hot, twirling mixture of ash, small pieces of pumice and other pyroclasts that are heavier than air and move down a volcano at high rates of speed.

# Chapter 3 Test Answer Key

Chapter 3 Test
Cones, Eruptions, and Pyroclasts

MATCHING

 1.  ___C___Lava A. Rough and fragmented lava flows 2.  ___E___Pahoehoe B. The most explosive eruption type. Ash plumes may reach 50,000 feet. 3.  ___B___Plinian C. Molten rock on the surface of the Earth 4.  ___G___Hawaiian D. Large pyroclasts-over 2 inches long with a rounded shape 5.  ___A___Aa E. Smooth and ropey lava flows 6.  ___F___Low Viscosity F. Thin and runny magma that usually erupts quietly with large amounts of lava. 7.  ___D___Bombs G. Eruption type in which thin and runny magma reaches the surface of the Earth through the main vent and fissures.

8-9. Name two reasons that volcanic eruptions occur.
Magma will rise to the surface of the Earth when it is less dense than the surrounding rock in the mantle. When the magma reaches the surface of the Earth the pressure difference between the gases in the magma and the surface pressures allows the magma to boil out.
This is like opening a can of pop when it has been shaken.

10-15. Name and draw the three kinds of volcanic cones.

Shield cone- Low and broad shaped cone formed from many eruptions of thin and runny lava.

Cinder ConeSteep sided cone formed from the ejection of pyroclastic materials.

Stratovolcano or composite cone- Formed from many alternating eruptions of ash and lava. Beautifully symmetrical cones.

16. What is a hot spot?
A hot spot occurs near the crust where very hot solid rock rises through the mantle (a mantle plume) and forms magma near the surface of the Earth. Hot spots form volcanoes in both oceanic plates and continental plates.

Fill in the blank with the correct answer. Use the following words to complete the blanks. Dust, Lava Tube, Mantle Plume, Ash, Caldera, Pyroclastic Flow, Blocks.

17. A large rough edged, angular pyroclast that is ejected during a volcanic eruption is called a block  .

18. A caldera  is a bowl-shaped depression caused by a volcanic eruption in which the top of the volcano collapses.

19. The smallest of the pyroclasts are called dust  . They may stay in the atmosphere for years.

20. A lava tube  forms when the surface of the lava cools and hardens, while the molten interior flows through and drains away.

21.  Ash  is the second smallest pyroclast. This material along with lava builds stratovolcanoes larger with repeated eruptions.

22. A mantle plume  is very hot, solid rock that rises through the mantle and will become magma as it reaches the surface of the Earth. They form hot spots.

23. A pyroclastic flow  is a very hot, twirling mixture of ash, gases, and small pieces of pumice and other pyroclasts that are heavier than air and move down a volcano at high rates of speed.

# Discussion Questions

## Thought and Discussion Questions

1. What caused the death of so many people during the second eruption of Vesuvius?

2. What is a pyroclastic flow?

3. Describe pahoehoe and aa lava flows.

4. What is a pyroclast and how do they form?

5. Write a definition for the following;
1) High viscosity 2) Low viscosity

### No Content Center Today!!

1. Name the six eruption types and the three cone shapes.

2. Describe how a:
Shield cone forms
Cinder cone forms
Stratovolcano forms

3. Draw diagrams to represent the six eruption types.

## Discussion Questions

1. What is a Hot Spot?

2. How does and hot spot form?

3. How does a caldera form?

# Discussion Questions

## Thought and Discussion Questions

1. What caused the death of so many people during the second eruption of Vesuvius?
Pyroclastic flows of 700 degree ash, gas, and pyroclasts moving of around 70 miles per hour swept over the city killing over 20,000 people.
2. What is a pyroclastic flow?
A turbulent mixture of very hot gas, ash, and pyroclasts flowing down the side of a mountain at from 70 -200 miles per hour.
3. Describe pahoehoe and aa lava flows.
Pahoehoe lava has a smooth and ropey texture. Pahoehoe forms when the lava flows at a slower speed, cooling slowly. Aa lava has a rough and fragmented surface. The lava forms when the lava flows at a fast speed, cooling quickly.
4. What is a pyroclast and how do they form?
Pyroclasts are
5. Write a definition for the following;
1) High viscosity 2) Low viscosity

### No Content Center Today!!

1. Name the six eruption types and the three cone shapes.

2. Describe how a:
Shield cone forms
Cinder cone forms
Stratovolcano forms

3. Draw diagrams to represent the six eruption types.

## Discussion Questions

1. What is a Hot Spot?

2. How does and hot spot form?

3. How does a caldera form?

# Lesson #7 Content Center

Content Center
Lesson #5 "Volcanoes"
Vesuvius "The Day it Rained Fire"

Pompeii and Herculaneum were bustling Roman cities in 79 A.D. Mt. Vesuvius hadn't erupted in over eight hundred years and the mountain was green with fig and olive trees. Farmers cultivated the sides of the cone. The people were used to earthquakes and didn't pay much attention to the numerous quakes that had been rattling their bowls and plates prior to the eruption. What they didn't know would kill thousands of people that beautiful August day in 79 A.D. Vesuvius was awakening from its long slumber.

Vesuvius awakened with a huge eruption of ash and pumice raining down on the city of Pompeii. Pompeii lay to the south of the volcano and that day the wind was from the north pushing the cloud toward the city. Pompeii was buried in up to 20 feet of pumice and ash. Many animals and people were suffocated and buried alive. Many people though, did survive the initial eruption. Some decided to flee but many stayed.

The city of Herculaneum lays to the west of the volcano and much closer to Vesuvius than Pompeii. Herculaneum was a beautiful beachside resort city in 79 A.D. Herculaneum was barely touched by the first eruption. In fact, about only one inch of ash and pumice fell on the city during the first eruption.
The next eruption was the deadly one. This eruption blanketed the whole surrounding area with very hot, turbulent, twirling gases and ash. This glowing cloud was very heavy and hugged the ground as it flowed down the side of Vesuvius. The temperatures of this pyroclastic flow were probably around 700 degrees F. and at a speed of over 70 miles per hour animals and people could not out run it. With temperatures this high everything in its path is killed instantly.
Herculaneum didn't get lucky this time. It was buried in an extremely hot flood of volcanic mud. This steam filled volcanic mud buried the city with a layer over 50 feet high. Pompeii suffered through this eruption also. Over 20,000 citizens died in the pyroclastic flows only hours after the initial eruption.
A man by the name of Pliny the Younger wrote an account of this eruption as he viewed Vesuvius from Naples to the northwest of the volcanic mountain. His account was probably the first one ever written. His uncle, Pliny the Elder, died in the second eruption that day. Pliny the Elder was a commander of a fleet of Roman battleships. He was also a naturalist, a person who studies natures spectacles and writes about them. He was viewing the eruption when he was probably over come by hot gases.
Today Vesuvius is the most visited volcano in the world. The mountain that hadn't erupted in about eight hundred years has erupted many times since. In 1631, Vesuvius belched out another pyroclastic flow, which has been the worst eruption since 79 A.D. Many tourists pay to make the very difficult climb to the crater to view the steaming lava inside the volcano. They flock to the excavated ruins of Pompeii and Herculaneum to view the plaster casts of bodies as they lay when they died almost two thousand years ago during the day that rained fire.
Discussion Questions

1. What caused the death of so many people during the second eruption of Vesuvius?

2. What is a pyroclastic flow?

# Lesson #7 Goals, Objectives, and Materials

Goals, Objectives and Materials
For Lesson #7
"Lava Flows and Pyroclasts"

### Goals:

To familiarize students with the vocabulary associated with volcanic processes and the structure of a volcano itself.

### Objectives:

The students will:

1. Become familiar with the processes and concepts that create and build volcanoes;
2. Become familiar with the terms associated with volcanic processes;
3. Become familiar with the vocabulary associated with the structure of a volcano.

### Materials:

1. Hands-On Lesson Plan Sheet

2. Five colors of modeling clay or playdough-Red, Brown, Gray, Black, Blue

3. 10 X 12 sheets of tag board

4. Felt tip pen for labeling

# Lesson #7 Hands-on Center

Hands-On Center
(Lava Flows and Pyroclasts)
Lesson #7
Modified and adapted from John Farndon's book
"How the Earth Works"

Flowing Lava

Materials

1. 4 plastic jars
2. 4 spoons
3. fine grained sand
4. stop watch
5. 4 plastic plates
6. 1 tablespoon
7. molasses
8. liquid dish soap
9. shampoo
10. vinegar

Part 1

The students will need their science notebooks, pencils, and stop watches ready. One student will measure one tablespoon full of one of the liquids. They will slowly pour that liquid onto a plastic plate. Another student will time how long it takes for the liquid to stop spreading. Repeat this procedure with the other three liquids.
The liquids that have the longest spreading times have the highest viscosities. Tell the students there are lavas with very low viscosities (very thin and runny) and lavas with very high viscosities (thick and pasty). There are also many different lavas in between.
Low viscosity lavas are found in Hawaii and Iceland and are usually not violent. High viscosity lavas are very violent and erupt with little or no lava. High viscosity lavas shoot pyroclasts such as pumice, cinders and ash high into the air.

Part 2
Have the students add one teaspoon of sand to one cup of the four liquids used in part 1.
Stir the mixture thoroughly.
Have the students repeat the pouring and timing portion as in part 1. Have all students record the times and compare Part 1 to Part 2 times.
Explain to the students that lavas with a high silica content(sand and quartz) have high viscosities(aa) and lavas with low silica contents have low viscosities (pahohoe)
Add sand to a cup of molasses until its viscosity is so high that will not flow. Spoon the mixture onto a dish and explain that they have just created a lava dome.
High or Low Viscosity

Materials:
1. 2 plastics jars
2. molasses
3. water
4. 2 straws

Fill a small plastic jar to within one inch of the rim with water and the other jar with molasses. Put one straw into each jar. Have one student blow bubbles with the same pressure. Record what happens. The students will see rapid bubbling in the water because the water has a low viscosity. This is what pahoehoe lava is like. The gases escape quickly from the low viscosity lava and usually are not very violent.
The students will see a slow bubbling from the molasses because of its high viscosity. Lava with a high viscosity will hold a lot of gas and will loose the gas as it nears the surface of the Earth and the pressures become lower (like opening a bottle of pop and releasing the pressure). These magmas erupt violently frequently.

Floating Rocks????
Materials:
Pumice
Clear plastic container
Water
Float pumice in a container full of water. Have the students draw what they see. Show the students the holes in the pumice explaining they were formed as the rock hurtles through the air.

# Lesson #8 Goals, Objectives, and Materials

Goals, Objectives and Materials
For Lesson #8
"Volcanic Cones and Eruptions"

### Goals:

To familiarize students with the processes involved in volcanic eruptions and how these eruptions form volcanic cones.

### Objectives:

The students will:

1. become familiar with the processes involved in volcanic eruptions;
2. become familiar with the way eruption types form volcanic cones;
3. become familiar with the differences in magma viscosity and how it relates to eruption explosiveness.

### Materials:

• Hands-On Lesson Plan Sheet

• Glass jar 9/10 filled with honey
• small cork
• Small steel ball (steel marble)
• modeling clay, playdough, or art clay
• popsicle sticks for shaping cones
• wax paper
• tag board
• colored markers

• # Lesson #8 Hands-on Center

Hands-On Lesson #8
(Volcanic Cones and Eruptions)
Why Does Magma Rise??
Materials: Glass jar 9/10 filled with honey
small cork
Small steel ball (steel marble)

The students will place a small cork and a small steel ball into an empty glass jar. The students will then fill the jar with honey and watch what happens. They should write down their predictions as to what will happen after the honey is placed in the jar. The students should write down what they see occurring and why they believe it happened..
The students will observe that materials made of less dense material (cork) will rise in a much denser medium (honey). The steel ball will remain on the bottom of the jar because it is denser than the medium that it is in (honey). Magma will rise in the Earth for the same reason, the magma is produced by the melting of the oceanic crust and the top layer of the mantle. The melting material is less dense than the surrounding mantle and that causes it to rise.

Cone Shapes
Materials:
1. modeling clay or playdough
2. popsicle sticks for shaping cones
3. wax paper

The students will construct a 3-d model of the three basic
volcano cone shapes using modeling clay or playdough.

1. shield cone

2. cinder cone

3. composite cone or stratovolcano

# Lesson #9 Content Center

Content Center
(Lesson #9)
Hot Spots-Hawaii and Yellowstone

Geysers and Hot Springs

Old Faithful geyser in Yellowstone Nation Park is a famous tourist attraction. Every hour or so it sends a stream of scalding hot water from 135-200 feet in the air. Why does this occur? The same scientific principle that makes a volcano erupt turns a hole in the ground into a spectacular fountain.
Hot springs and geysers form over magma chambers in very similar ways. Geysers though, are more complex in how they form and much more spectacular in the display that they put on. Here is how the Earth works like a giant hot water heater and boiler.
Rain water seeps into the ground and slowly percolates down through cracks in the layers of the upper crust. Here it collects in porous rock that holds the water like a sponge.
The huge magma chamber that sits under the park is the heating source. This magma chamber is located over two miles below the porous rock layer that holds the water. The rock below radiates the heat up to the water by a method called conduction. You have felt conduction when you have picked up a glass handled dish of hot water from the microwave oven. The glass handle is hot because the heat from the water radiates through the bowl to the handle.
The water in the layer of porous rock is heated but will not boil because it is under extreme pressure from the overlying rock. The water is superheated like in a steam boiler. The temperatures may reach over 500 degrees Fahrenheit! At the same time that the water is heating, more water from the surface keeps coming into the rock layer. This cooler water sinks to the bottom causing the hot water to rise. When the water rises the pressure from the surrounding rock layers drops. The result is the hot water will continue to rise untill it reaches the surface of the Earth. Some of these hot springs become filled with mud and form hot mud pots. People throughout the world come to hot springs and mud pots for enjoyment and some even believe they have medicinal or magical healing powers.
Geysers, the giant boilers of the Earth, are produced in a slightly more complex way. As the heated groundwater rises it collects in rock pockets that are under extreme pressure. Because of the high pressure the water is not able to boil. The temperature continues to rise until some of the water boils. The steam then rises very fast and takes some of the non-boiling water with it. This reduces the pressure in the rock pocket. Thr superheated groundwater then heats to steam quickly because of the drop in pressure around it. When this happens the rest of the water in the rock pocket explodes out through the fissure and will continue to erupt until the steamy groundwater is gone.
Sometimes these eruptions will last for over an hour. When the eruption is over the rock pocket will fill with groundwater and start the cycle again.
Old faithful in Yelowstone Nation Park goes through this cycle every 65 minutes or so.

Questions

1. What is the difference between a hot spring and a geyser?

2. Why does the release of pressure cause the geyser to erupt so explosively?

# Lesson #9 Goals, Objectives, and Materials

Goals, Objectives and Materials
For Lesson #9
"Hot Spot Volcanoes-Hawaii and Yellowstone"

### Goals:

To familiarize students with the vocabulary and
processes involved in understanding hot spot
volcanism.

### Objectives:

The students will:

1. become familiar with the processes of plate
movement that causes hot spot volcanoes to
form;
2. become familiar with the processes that
cause mantle plumes to form and rise.

### Materials:

1. One "Content Center Lesson" for each student

2. Hands-On Lesson Plan Sheet

3. Cooking Oil
4. Squeeze Bottle (Example: dish soap bottle)
5. Large Clear Plastic Container
6. Water
7. Red Food Coloring

# Hands-on Center

(Hot Spots: Hawaii and Yellowstone)
Lesson #9

The mantle's convection experiment
Modified and adapted from John Farndon's book
"How the Earth Works"

### The teacher must set up and run this experiment! The oil and dish will get hot!!!!!

Materials:

1. 1 heat proof glass dish
2. 1 tea candle
3. 3 cups of cooking oil
4. 1 book of matches
5. 1 bottle of dark colored food coloring
6. 1 eye dropper
7. 2 clay bricks
8. 4 small pieces of packing foam

1. Pour the 4 cups of cooking oil into the glass dish.
2. Place the glass dish onto the 2 clay bricks.
3. Light the tea candle and place it under the glass dish.
4. Put dark colored food coloring into the eyedropper.
5. Squeeze some of the food coloring into the cooking oil near the bottom of the glass dish.
6. When the food coloring begins to move lay some pieces of Styrofoam on top of the cooking oil and observe the movement. (The flowing of the Styrofoam will represent the movement of the Earth's plates) The cooking oil will heat up and convection currents will be generated. The food coloring will enable the students to see the movement of the convection currents. The oil and food coloring will rise as they heat up. The rising material will cool as it nears the surface of the liquid. The farther the material gets from the heat source the cooler it will become. As the material cools it will slowly desend.
This process of gaining energy (heat) and rising and then losing energy (cooling) will go on and on. These are convection currents. This rising and cooling sets up a current in the cooking oil. The teacher should explain that this is a theory of how the mantle "flows" and the plates (Styrofoam pieces) of the Earth are carried with these movements.
The students should draw and label a diagram of the experiment.

Magma Rising
Materials:
1. Cooking Oil
2. Squeeze Bottle (Example: dish soap bottle)
3. Large Clear Plastic Container
4. Water
5. Red Food Coloring
1. Have the students fill a plastic squeeze bottle full of cooking oil with red food coloring in it.
2. Place the squeeze bottle into a large clear plastic container full of water.
3. Tell the students to squeeze slowly the bottle full of cooking  oil.
1. Have the students record what they observe.
The students will observe the cooking oil rise through the water because the oil is less dense than the water. The same process causes magma in the Earth to rise from the bottom of the Mantle to the Earth's crust causing volcanism.