Download CHAPTER 18 Volcanism

Name______________________________________
CHAPTER
180 points
18 Volcanism
SECTION 18.1 Volcanoes
In your textbook, read about the anatomy of a
volcano and volcanic material.
Circle the letter of the choice that best completes
the statement or answers the question.
Date
Class period
3. In your textbook, read about types of volcanoes.
10-25 Identify the type or types of volcano being described as shield
volcano, cinder-cone volcano, or composite volcano.
volcano.
25 points
1. Lava erupts through an opening in Earth’s crust called a
a. vent.
b. crater.
c. caldera.
d. volcano
10._________________ 11.________________
12._______________
2. A bowl-shaped depression that forms around the vent of a volcano is a
a. magma chamber. b. vent. c. crater.
d. sill.
_______________13. Forms when small pieces of magma are ejected
3. Broad, gently sloping volcanoes with quiet eruptions are called
a. composite volcanoes. b. cinder cones. c. hot spots. d. shield volcanoes.
_______________14. Has broad, gently sloping sides and a nearly
4. The most explosive volcanoes are
a. hot spots.
c.
b. composite volcanoes.
d.
_______________15. Forms when layers of basaltic lava accumulate
5. Most volcanoes form
a. at hot spots.
b. at plate boundaries.
cinder cones.
sheild volcanoes.
c. in the middle of continents.
d. in the center of ocean plates.
b. pyroclastic flow
c. caldera
circular base
during a nonexplosive eruption
6. Which of the following forms when the top or side of a volcano collapses
into the magma chamber?
a. dike
into the air then fall back to Earth and pile up
around a vent
d. vent
7. ________ form(s) where plates move apart.
a. Hot sports
c. Subuction zones
b. Divergent volcanism
d. Convergent volcanism
8. When magma reaches Earth’s surface, it is called
a. a vent. b. a pyroclastic flow c. lava. d. calderas.
9. Volcanoes that form far from plate boundaries are associated with
a. subduction zones.
c. ocean ridges.
b. divergent boundaries.
d. hot spots
_______________16. Mauna Kea in Hawaii is an example.
_______________17. Small volcano with steep sides
_______________18. Forms when layers of tephra alternate with lava
_______________19. Forms from lava that contains relatively small
amounts of gases and silica
_______________20. Forms from lava that is higher in water and silica
content than lava that forms shield volcanoes
_______________21. Fueled by magma that contains large amounts
of silica, water, and gases
_______________22. Magma that fuels this type of volcano contains
large volumes of gases but not silica and water.
_______________23. Potentially the most dangerous to humans and
most destructive to the environment
_______________24. Mount St. Helens and Mount Rainier are
examples.
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 1
Name______________________________________
SECTION 18.1
Volcanoes, continued
25 points
Date
Class period
Reviewing Vocabulary
In your textbook, read about where volcanoes occur.
Use each of the terms below just once to complete the passage.
Hawaiian Islands crust divergent flood basalts hot spots
Iceland mantle volcanoes plateau ocean ridges
Circum-Pacific Belt western convergent
Most of the world’s volcanoes form along (25) ___________
plate boundaries. Slabs of oceanic crust descend into the
______________ and melt. The magma that forms is
forced upward through the overlying plate and forms (27) ______
when it reaches Earth’s surface. The (28) _______________
(26)
marks the locations of most convergent boundary volcanoes. It
stretches along the (29) ________________ coasts of North
and South America and down the eastern coast of Asia.
At (30) _________________ plate boundaries, magma
is forced upward into fractures and faults that form as plates separate or
spread apart. Most of the volcanoes that form along divergent
boundaries are located underwater along (31) _____________.
This type of volcanic activity can be observed above sea level in
caldera hot spots
vent
viscosity
pluton
tephra
crater
For each item described in Chapter 18 write the word from the box
_________________1. Volcanic fragments thrown into air during a
volcanic eruption
_________________2. Internal resistance to flow
_________________3. Intrusive igneous rock body
_________________4. Opening in Earth’s crust through which lava
erupts
_________________5. Bowl-shaped depression around a vent at the
top of a volcano
_________________6. Depression that forms when the top or side of
a volcano collapses into the magma chamber
_________________7. Unusually hot areas in the mantle that are
stationary for long periods of time.
Label the illustration using terms from Chapter 18.
(32) _________ , which sits atop the Mid-Atlantic Ridge.
Some volcanoes that form far from plate boundaries form over
(33) _____ __________, which are unusually hot regions of
Earth’s mantle. At hot spots, high-temperature plumes melt rock. The
magma that forms moves upward toward the (34) _________ and
melts the crust to form a volcano. As a tectonic plate moves over a hot
spot, a string of volcanoes forms.
The (35) _____________________ are forming as
the result of a hot spot. Hot spots can also result in the formation of
(36) _______
_______ , which erupt from fissures to form a
flat plain or a (37) ___________rather than volcanic mountains.
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 2
Name______________________________________
CHAPTER
Date
20 Mountain Building
SECTION 20.1
Class period
The Birth of the Himalayas
Crust–Mantle Relationships
In your textbook, read about Earth’s topography and the
relationships between the crust and the mantle.
Write an answer that best completes the statement or
answers the question.
1. Approximately how much of Earth’s surface is below sea
level?
30 points
2. Approximately how much of Earth’s surface is above sea level?
3. The largest percentage of Earth’s surface above sea level ranges in
elevation from 0 km to
4. How far below sea level is the largest percentage of Earth’s surface?
5. Describe the kind of rock and density of the oceanic crust.
In your textbook, read about isostasy and erosion.
Use each of the terms below just once to complete the passage.
equilibrium
isostatic rebound
mantle
mountains
roots
seamounts
smaller
Isostasy is a condition of (6)_________________between the mass
of Earth’s crust and the buoyancy of the mantle. Topographic highs in
the crust have deep (7) _________________ that extend into the
mantle and provide buoyant support. Continents are said to float on the
denser (8) _________________ .
As (9) _________________ rise, deep roots form. As mountains
are eroded, their roots become (10) _________________. As material is
removed from mountains by erosion, the crust slowly rises. This process
known as (11) _________________ . Such crustal movements resulting
from isostasy are not restricted to continents, but also occur when volcanic
mountains on the seafloor, called (12)_________________, form.
The greatest challenge for mountain climbers is Mt. Everest, whose peak rises
8,872 meters above sea level. This is the highest mountain in the world, though many
mountains around it are almost as high. Mt. Everest is in the Himalayas, a series of
massive ranges that extends 2,500 kilometers across South Asia north of India. The
Himalayas cover all or part of the countries of Tibet, Nepal, and Bhutan.
A climber on the high slopes of Mt. Everest would probably be surprised to learn
that the region was relatively flat about 40 million years ago. It was then that two
continental plates collided. The plate carrying India had been moving northward for
millions of years. The oceanic crust in front of it was slowly subducted under the
Eurasian plate. But when the two continents collided, subduction stopped because
India could not sink into the mantle. Instead, it pushed crust upward and downward.
The Himalayas were one result. Thus, the Himalayas are actually pieces of plates
broken and lifted up because of the collision. Another result of this collision was the
movement of China eastward, as the movement of India northward pushed the
Eurasian plate in front of it. The collision is still occurring today. In fact, the
Himalayas are growing in elevation at a rate of about 1 centimeter per year.
Answer the following questions.
1. Where are the Himalayas?
2. What was the area of the Himalayas like 40 million years ago?
3. How did the movement of plates create the Himalayas?
4. What else resulted from the collision of those plates?
5. What type of plate boundary exists today along the Himalayas?
6. If the Himalayas continue to grow in elevation at their present rate,
how tall will Mt. Everest be in one million years?
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 3
Name______________________________________
SECTION 20.2
Convergent–Boundary
Date
30 points
Class period
Mountains
In your textbook, read about mountains that form as the result of convergence.
Use the terms below to label the diagrams. On the line below each
diagram, write the name of the type of boundary pictured.
continental crust deformed sediments fault basin sediments
magma island arc complex volcanic mountains mantle
oceanic crust
subducting plate
trench
20. Which convergent plate boundary does not include a subduction
continental crust trench magma oceanic crust
sediments subducting plate volcanic mountains
zone? Why? not form as the result of continental-convergence
Use
the two plates have the same density be sub
21. How can oceanic sediments become part of continental
mountains?
22. How do the mountains that form along an oceanic-oceanic convergent
boundary differ from those associated with an oceanic-continental convergent
boundary?
Mo
oceanic-oceanic boundary
23. Briefly describe the events that led to the formation of the Appalachian
Mountains.
20. Which convergent plate boundary does not include a subduction zone?
. An island
Why?
21. How can oceanic sediments become part of continental mountains?
Oceanic sediments may fill the area between a trench and the coast
to form mountains.
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 4
Name______________________________________
SECTION 20.3
30 points
Other Types of Mountains
In your textbook, read about
divergent–boundary and
nonboundary mountains.
For each item write the word
from the box
Tetons
Basin and Range Province
fault-block mountain
Mauna Kea
ocean ridge
pillow basalts
uplifted mountain
solitary volcanic peaks
Date
Class period
In your textbook, read about nonboundary mountains.
Answer the following questions.
11. What makes uplifted mountains, fault-block mountains, and hotspot volcanoes different from other mountains?
They generally form far from
12. Describe the rocks that make up uplifted mountains. How are these
rocks different from rocks associated with plate-boundary orogeny?
The rocks of uplifted mountains show little deformation,
unlike the rocks
_________________ 1. Region of very broad uplift at a
.
divergent plate boundary on the ocean
floor
_________________ 2. Igneous rocks that form along ocean
ridges
_________________ 3. Forms when a large region of Earth’s
crust is uplifted as a unit
_________________ 4. Example of uplifted mountains
13. Describe how fault-block mountains form.
_________________ 5. Forms when large pieces of crust are
Province.
Fault-block
, uplifted, or
.
14. Describe and classify the mountains of the Basin and Range
tilted, uplifted, or dropped between large
faults
_________________ 6. Example of fault-block mountains
_________________ 7. Form when plates move over hot spots
in Earth’s mantle
_________________ 8. Example of hot-spot volcanic peak
Answer the following questions.
9. What causes regional uplift?
Heat from the mantle causes the overlying crust to rebound, or
upward
10. How do mountains form over hot spots?
As a tectonic
The mountains of the Basin and
15. How did the mountains of Hawaii form?
16. Which type of mountains are the Wasatch Mountains of Utah?
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 5
Name______________________________________
20 points
Date
Class period
Applying Scientific Methods
Thinking Critically
Read a geologist’s report below on one area of Alaska. Then use
the information in the report and the cross-sectional diagram of
central Alaska to answer the questions.
Use the map of the Hawaiian Islands to answer the following questions.
The dates on the map represent the approximate times (millions of years
before the present [M.Y.B.P.]) that the islands formed.
The central Brooks Range of Alaska is an area of rugged, east-trending ridges
with heights of up to about 2500 m. This range, which stretches across northern
Alaska, is part of the Rocky Mountain system. Sedimentary rocks are common in
the Brooks Range. These rocks are complexly folded and faulted in the Brooks
Range and are less deformed elsewhere. Some marine sedimentary rocks contain
small fossils of invertebrates, shells, and corals and are found near the mountains’
summits of the Brooks Range. The fossils provide information that is useful in
dating rocks and establishing the geological sequence.
Metamorphic rocks, such as marble and dolomite, are found along the south
side of the range. Several episodes of uplift, deformation, and intrusion have
produced complexly folded, fractured, and thrust faulted blocks. Erosion and
heavy glaciation account for the rugged mountain profiles and U-shaped valleys
evident today.
1. Describe the kind of orogeny that formed these islands that are far from
tectonic plate boundaries.
2. According to the map, which island is the oldest?
Which is the youngest?
3. Where would you expect the next island in the group to form?
1. Note that the mountains’ roots extend into the mantle. Which
mountain range has the greatest mass above Earth’s surface?
2. From the diagram, what type of plate boundary exists in the south?
Describe its location and mark the place on the map.
4. How do the shapes of the mountains in this complex differ from the shapes
of volcanoes in large mountain ranges?
3. How does the Chugach Range appear to have formed?
4. From the evidence presented in the report, how do you think the
Brooks Range formed? What led you to this conclusion?
5. How does the formation of these mountains change the underlying
crust?
5. How can you explain the presence of marine sedimentary rock in the
Brooks Range?
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 6
Name______________________________________
Date
20 points
The Dynamic Earth
Class period
UNIT 5 STUDY GUIDE FOR CONTENT MASTERY
Match the geologic phenomenon or process below with the correct
group of terms.
earthquake
intrusive activity orogeny
plate tectonics
volcano
_________________ 1. Seafloor spreading, ridge push, slab
pull
_________________ 2. Batholiths, stocks, laccoliths
_________________ 3. Caldera, crater, hot spot
_________________ 4. Fault, seismic waves, epicenter
_________________ 5. Folding, faulting, uplift
12. Explain how mantle plumes provide evidence for the rate and
direction of tectonic plate motion. Draw an arrow on the diagram to
help explain the process.
Use each of the terms below to complete the statements.
convection currents faults
hot spot
magnetic patterns
modified-Mercalli scale
volcanoes
6. Evidence of seafloor spreading is provided by
symmetric_________________ of ocean-floor rocks.
7. Plate movements are related to ______________ in Earth’s
mantle that cause warm matter to rise and cool matter to sink.
8. Cinder-cone, shield, and composite are three types of
_________________.
9. Earthquakes occur when stress in rock is released at breaks in
Earth’s crust called _________________.
10. An earthquake’s intensity, or the amount of damage it causes, is
measured on the _________________.
11. A solitary volcanic peak may form when a plate moves over a
_________________ in Earth’s mantle.
13. Describe evidence that the Yellowstone Hot Spot Volcano has
moved in geological time.
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 7
6
Name______________________________________
Mountain Building
Across
6. pluton that cuts across preexisting rocks and often forms when magma
invades cracks in surrounding rock
7. batholiths, stocks, sills, or dikes
8. unusually hot area in Earth's mantle that is stationary for long periods of time
where higher temperature plumes of mantle material rise toward the surface
10. igneous rock formed when magma pushes through dikes and erupts onto
the seafloor
12. pluton that forms when magma intrudes parallel rock layers
13. large, igneous rock mass that is common in the interior of major mountain
chains
16. large crater that can form when the summit or side of a volcano collapses
into the magma chamber during or after an eruption
18. bowl-shaped depression that forms around the central vent at the summit
of a volcano
19. what is built by volcanoes or when land is pushed upward by earthquake
faults; as described in chapter 20 in the textbook
20. irregular shaped pluton smaller than a batholith that cuts across older rocks
Down
1. slow process of Earth's crust rising as the result of the removal of mass from
the crust
2. relatively smaller, mushroom-shaped pluton that forms when magma
intrudes into parallel rock layers close to Earth's surface
3. opening in Earth's crust through lava erupts and flows out onto the surface
4. large sloping volcano built by violent eruptions of volcanic fragments and
lava that accumulate in alternating layers
5. condition of equilibrium that describes the displacement of Earth's mantle by
Earth's continental and oceanic crust
9. rock fragments that are thrown into the air during a volcanic eruption and fall
to the ground
11. broad volcano with gently sloping sides built by nonexplosive eruptions of
basaltic lava that accumulates in layers
14. type of mountains that form when large pieces of crust are tilted, uplifted, or
dropped downward between large normal faults
15. steep-sided smaller volcano that is built by the accumulation of tephra
around the vent
17. cycle of processes that form all mountain ranges, resulting in broad
mountain belts, most of which are associated with plate boundaries
2
Date
Class period
12
13
20
10
15
11
4
Created by Puzzlemaker at DiscoveryEducation.com
14
Standard 2: Students will understand Earth’s internal structure and the dynamic nature of the tectonic plates that form its surface.
Objective 2: Describe the development of the current theory of plate tectonics and the evidence that supports this theory.
Objective 3: Demonstrate how the motion of tectonic plates affects Earth and living things.
Page 8