Parts of a Volcano
Volcanic Landforms
Vocabulary
The Creation of Volcanoes
Eruptions
100
What is lava?
Lava is magma that flows out onto Earth's surface.
100
what three kinds of landforms are created by the eruptions of volcanoes? Name all.
There are 3 types of volcanic landforms: Cindercone, Shield, and Composite
100
What is Magma?
Molten rock beneath the earth's surface.
100
Where do most volcanoes occur?
Most volcanoes, like most earthquakes, occur along the boundaries between shifting tectonic plates. (Ring of Fire)
100
What are active volcanoes?
Active volcanoes are the volcanoes that erupt constantly.
200
What are magma chambers?
Magma chambers are reservoirs from which volcanic materials erupt.
200
What is a cinder cone volcano?
This type of volcanic landform is made up of small rock particles, or cinders. It is characterized by a small cone with steep sides.
200
What is silica?
A compound in magma made of oxygen and silicon.
200
Why does the rock in the mantle melt?
As the tectonic plate moves under another (subduction zone), the rock in the mantle melts and becomes magma.
200
What are dormant volcanoes?
These volcanoes have become inactive, but people are not certain that they will not erupt again.
300
what is a vent? where is it located?
Openings through which volcanic materials erupt are called vents. They are located near the peak of the mountain.
300
What is a shield volcano?
This type of volcano is made up of layers of lava rocks. it's not as steep as cinder cone volcano and is created slowly that's why it has gentle and broad sides.
300
What is a hot spot?
A region of volcanic activity in the middle of a tectonic plate.
300
Why does magma rise?
magma, the melted mantle, rises because it is filled with gas and is less dense than the solid rock around it (it's buoyant)
300
What are explosive eruptions?
Extremely violent eruptions that erupt lava, ash, and usually have a pyroclastic flow.
400
What is the pyroclastic flow?
A cloud of ash, embers, and poisonous gas that flow from an explosive eruption.
400
What is a composite volcano?
This type of volcanic landform is made up of layers of lava flows alternating with layers of ash, cinders, and rocks. it is a combination of cinder cone and shield volcanoes.
400
What is a caldera?
A crater made when a volcano erupts violently or caves in.
400
what prevents magma from gradually and slowly rising to the peak of the mountain constantly?
The rocks above magma press down on the magma and create great pressure. When the pressure is released, volcanic materials suddenly erupt and move out to the surface.
400
What are Extinct Volcanoes?
Volcanoes that have not erupted in recorded history are considered to be extinct volcanoes.
500
Define Subduction Zone. Where is it located?
subduction occurs when two plates collide. the denser; heavier, palte slides under the other plate and becomes part of the mantle.
500
Which type of volcanic landform is the most destructive? Name a volcanic landform that was developed this way.
Composite volcano. Mt. St. Helens is a composite volcano.
500
what is Ring of Fire and where is it located?
A zone of frequent earthquakes and volcanic eruptions that encircles the Pacific Basin.
500
How do hot spots form new land? Name a landform created by hot spots.
Hot spots erupt and release magma. As magma comes out it becomes lava and hardens into landforms. Hawaiian islands are created by hot spots.
500
How do the types of volcanic eruptions (quiet and explosive) differ?
Quiet: Lava oozes over the sides of the volcano. Not many deaths, can destroy land. Explosive: Ash, volcanic bombs, rock, lava violently are thrown from the vent of the volcano. Many people are killed in this type of eruption. Land destroyed.
M
e
n
u