What is weak spot in Earth's crust where magma,(molten material) comes to the surface?
Volcano
100
What is the inward collapse of a volcano?
Caldera
100
Beneath a volcano, the magma collects in a pocket called a...
Magma chamber
100
The content which determines how explosive a volcanic eruption can be is...
Silica content
100
How did the San Andreas fault form.
As plates slide past each other, they push and pull on the crust with an enormous force. This makes the crust break which forming faults.
200
A mountain where lava flows gradually build a wide,gently sloping volcano called...
Shield volcano
200
What forms when magma hardens inside of a volcanoes pipe?
Volcanic neck
200
Magma travels from the magma chamber through a long tube called a...
pipe
200
Geologists classify volcanic eruptions in 2 groups. The groups are...
quiet and explosive
200
( True/False) All of the volcanoes in North America form from colliding boundaries...
True
300
Material such as ash, cinder, and bombs build up around the vent in a steep, cone-shaped hill or a small mountain called...
Cinder cone volcano
300
An intrusion forms when magma hardens underground to form igneous rock. True or false an intrusion is always younger that the rock around it...
true
300
Molten rock and gas leave through an opening at the top of the volcano which is called a...
Vent
They can also leave through side vents
300
What terms do the geologists use to determine a volcano's stage in a life cycle?
Active,dormant,and extinct
300
How did the Sierra Nevada form?
The force of the plate motions pushed the batholith up forming the mountains we know today.
400
Tall,cone-shaped mountains in which lava flows generally alternate with layers of ash...
Composite volcano
400
Two types of intrusions are dikes and sills. What is the difference between a dike and a sill?
Dike: Magma forces itself across layers and hardens.
Sill: Magma squeezes between horizontal layers of rock.
400
What is a lava flow?
A lava flow is the area covered by lava as it flows out of the vent.
400
A pyroclastic flow is a type of explosive that hurls out a mixture of...
hot gases,ash,cinders,and bombs
400
What is a basin?
A basin is a broad-shaped valley.
500
Which volcano is high in silica and low in silica?
High: Cinder cone
Low: Shield
500
What is a large mass of rock that cools inside the crust?
Batholith
ex: Sierra Nevadas
500
A bowl-shaped area that may form at the vent is a...
crater
500
What is a geyser and how does it form?
A geyser is a fountain of water and steam that erupts from the ground.
A hot spring form when bodies of water deep underground gets heated by a nearby body of magma or hot rock. The hot water rises to the surface and collects in a natural pool. Sometimes when rising, the water and steam can become trapped in a crack. Pressure builds until the mixture suddenly sprays above the surface.
500
How did Central Valley form?
The Sierra Nevada and Coast Ranges are on both sides of the valley. As these mountains rose, the crust forming the Central Valley's floor was bent downward. Over time, a thick layer of sediment built up on the floor