A volcano is a place where molten rock, _________, and solid rock erupt through an opening in the crust.
hot gases
100
Many of Earth's volcanoes are at the ocean floor lining the ____________.
Mid ocean ridges
100
As gases and lava explode out, hot rocks fall to the ground and build up a steep-sided pile called a ______________.
Cinder Cone Volcano
100
Magma hardens in vertical cracks to form a ___________
Dike
100
An opening in the ground through which hot water and steam erupt periodically is called a ___________.
Geyser
200
Magma erupts through a central opening called a ______.
Vent
200
Most volcanoes occur along _________ boundaries where subduction occurs.
Convergent Plate
200
Magma that flows out of a vent forms a ____________ as the lava hardens into a wide, flat mound.
Shield Volcano
200
Magma that cools and hardens between horizontal layers of rock forms a ___________.
Sill
200
An opening in the ground where hot water and gases form a pool is called a _________.
Hot Spring
300
When magma erupts through the Earth to the crust it is called _______.
lava
300
Where plates are moving apart volcanoes form. - name the place
Rifts which occur at mid-ocean ridges
300
Eruptions that alternate between explosive and quiet periods cause a ___________ to form.
Composite Volcano or Stratovolcano
300
A small pluton and dome-shaped __________ occurs when magma in a horizontal crack in the ground pushes upward because it is very thick and can't spread out.
Laccolith
300
Heat from below the Earth's Surface is called __________.
Geothermal Energy
400
A cup-like hollow around the vent located at the top of a volcano is called a ________.
crater
400
A _________ created the Hawaiian Islands.
Hot Spot
400
A volcano that is erupting now or has erupted recently is said to be ____________.
Active
400
Example of Batholith
Half Dome
400
The first geothermal power plant in the United States produced steam that was used to produce _________.
Electricity
500
When a volcano collapses it forms a very wide crater called a _________.
Caldera
500
Another name for Circum-Pacific volcano belt
Ring of Fire
500
What is the difference between a dormant and an extinct volcano?
Dormant has erupted during recorded history, extinct has not and is heavily eroded.
500
The largest and deepest of all underground formations.
Batholith
500
Sometimes water evaporates quickly out of hot springs and the remaining water may become thick with broken rocks and minerals. This forms a hot bubbling pool called a _________.