What is a weak spot in the crust where molten material, or magma, comes to the surface?
That weak spot is a volcano
100
Why do people want to live near a volcano?
People want to live near volcanoes because of the great soil. All of the eruptions leave great nutrients that plants and crops need to grow.
100
What are the the five parts inside a volcano?
The five parts are the magma chamber, pipe, vent, lava flow, and crater
100
How does a shield volcano form?
A shield volcano forms when lava flows gradually builds a wide, gently sloping mountain.
100
What is silica?
Silica is a material found in magma that is formed from the elements of oxygen and silicon.
200
What is a sill?
A sill is a slab of volcanic rock formed when magma squeezes between layers of rock.
200
If a volcano is low in silica what type of eruption is it?
If a volcano is low in silica it is a quiet eruption
200
What are the thee types of terms geologists use to determine a volcano's stage of activity?
Geologists use the terms dormant, active, extinct to describe a volcano's stage of activity.
200
What are the features formed by magma?
The features include volcanic necks, dikes, sills, and batholiths
200
What are examples of igneous intrusions?
Dikes and sills are examples of igneous intrusions.
300
What volcano is it that lava flows gradually builds a wide, gently sloping mountain?
The volcano is a shield volcano
300
What do lava flows of pahoehoe and aa indicate about the type of volcanic eruption that occurred?
Pahoehoe and aa indicates the surface's shape
300
Where are hot springs and geysers often found?
Hot springs and geysers are found in areas of present or past volcanic activity
300
When a volcano's lava is high in silica what does it produce?
It produces ash, cinders, and bombs.
300
Are volcanic belts formed along the boundaries of Earth's plates?
True or False
400
What is a caldera?
A caldera is a huge hole left by the collapse of a volcanic mountain
400
What is the consistency of high-silica magma?
High-silica magma is thick and sticky.
400
Where do molten rock and gas leave the volcano through an opening?
All the substances leave through a vent
400
What are the three main type of volcanoes?
The three main types of volcanoes are shield volcanoes, are cinder cone volcanoes, and composite volcanoes
400
Is an intrusion always younger than the rocks around it?
True or False
500
What is the type of explosive eruption that hurls out a mixture of hot gases, ash, cinders, and bombs?
The eruption is a pyroclastic flow
500
What is one specific instrument that geologists use to monitor volcanoes?
Geologists use tilt meters
500
What happens when a volcano erupts?
When a volcano erupts the force of the expanding gases pushes magma from the magma chamber through the pipe until it flows or explodes out of the vent.
500
Where are faults located?
Facts are located near the boundaries of plates
500
What is a crater?
A crater us a bowl-shaped area that may form at the top of volcano around the central vent.