a molten mixture of rock-forming substances, gases, and water from the mantle
What is magma?
100
a type of explosive eruption that hurls out a mixture of hot gases, ash, cinders, and bombs
What is a pyroclastic flow?
100
a dead volcano that is unlikely to erupt again
What is an extinct volcano?
100
a volcano forms over a hot spot when magma erupts through the crust reaches the surface
How does a hot spot volcano form?
100
a long tube in the ground that connects to Earth's surface is a _________
pipe
200
a volcano that scientists expect to awaken in the future and become active
What is a dormant volcano?
200
-this can bury entire towns when it erupts out of a volcano
-if it becomes wet, can cause roofs to collapse
-a jet plane can suck in this and cause it to stall
How does volcanic ash cause damage?
200
a mass of rock formed when a large body of magma cools inside the crust
What is a batholith?
200
the properties of magma depend on the amount of silica in magma
What properties of magma help to determine the type of eruption?
200
a(n)______ is a bowl shaped area that may form at the top of a volcano around the central vent
crater
300
this forms when magma hardens underground to form igneous rock
What is an intrusion?
300
these are important because after a volcano erupts, it leaves behind it and, people can use this super fertile soil, which can support plant growth
How are volcanic soils important?
300
a broad, bowl-shaped valley
What is a basin?
300
these features are volcanic necks, dikes, sills, and batholiths
What features form as a result magma hardening beneath Earth's surface?
300
______ is a material found in magma that is formed from the elements oxygen and silicon
silica
400
a huge basin in California with the Sierras and Coast Ranges on either side
What is the Central Valley?
400
these mountains formed by volcanoes occurring where an oceanic plate and a continental plate collide
How did the volcanoes in the Andes Mountains form?
400
a string of islands formed by the volcanoes along a deep-ocean trench
What is an island arc?
400
the four features are faults, volcanoes, mountain ranges, and basins
What four features of California geology does plate tectonics explain?
400
a(n) _____ is the huge hole left by the collapse of a volcanic mountain
caldera
500
an area where material from deep within the mantle rises and then melts, forming magma
What is a hot spot?
500
the pressure in magma decreases as it reaches the surface
What happens to the pressure in magma as the magma rises toward the surface?
500
a pocket where magma collects in a volcano
What is a magma chamber?
500
most of these are located along spreading and colliding boundaries
Where are most volcanoes located?
500
a fountain of water and steam that erupts from the ground is a _______