a weak spot in the Earth's crust where molten material, or magma, comes to the surface
What is a volcano?
100
a pocket beneath a volcano where magma is collected
What is a magma chamber?
100
active, dormant, extinct
What is the life cycle of a volcano?
100
shield volcanoes, cinder volcanoes, composite volcanoes, and lava plateaus
What are the landforms made of lava and ash?
100
it is found along plate boundaries where crust is pushed and pulled with enormous force until it breaks
What is a fault?
200
a molten mixture of rock-forming substances, gases, and water from the mantle
What is magma?
200
thick sticky magma that produces explosive eruptions
What is high silica magma?
200
a fountain of water and steam that erupts from the ground
What is a geyser?
200
a huge hole left by a collapsed volcanic mountain
What is a caldera?
200
it can form when a plate is being subducted under another
What is a volcano?
300
a string of islands resulting from volcanoes
What is an island arc?
300
thin and runny magma that creates quiet eruptions
What is low silica magma?
300
water underground is heated by magma, the water rises and collects in a natural pool, the hot water and steam becomes trapped in a crack, and then the pressure builds until it sprays above the surface
How are hot springs and geysers formed?
300
it forms when magma hardens underground to from igneous rock which is always younger than the rocks around it
What is intrusion?
300
it results of plate motion, folding and pushing the crust upward
What is a mountain range?
400
an area where material from deep within the mantle rises and the melts, forming magma.
What is hot spot?
400
magma collects in the magma chamber, then it flows through the pipe, and then finally erupts through the vent/crater
What is the passage way in which magma moves to reach the surface?
400
the eruption buries everything in its path with a thick layer of lava
What are the hazards of a quiet eruption?
400
volcanic necks, dikes, sills, and batholiths
What are the features formed by magma?
400
a broad bowl-shaped valley
What is a basin?
500
two areas where most volcanoes form, along Earth's plates
What are spreading and colliding boundaries?
500
dissolved gases form bubbles as the magma rises and when the pressure falls within the magma the bubbles expand and exert an enormous force pushing the magma upward
What causes a volcano to erupt?
500
during the eruption the volcano sends out deadly gases, ahs, cinders, and bombs which can bury entire towns
What are the hazards of and explosive eruption?
500
volcanic soil is very fertile because when the volcanic ash breaks down it releases potassium, phosphorous, and other substances plants need to grow
Why do people risk living near active volcanoes?
500
the movements of the Pacific and North American plates produced California's major geological features
What formed California's major geological features?