What is a volcano?
An opening in the Earth's surface.
What is the difference between magma and lava?
Magma is molten lava under Earth's surface, and lava is when it comes out of the volcano.
What is root wedging?
What is a landslide?
soaked land (dirt and plants) becomes uprooted and falls down a hill or mountain
What are the three layers of the Earth?
Core, mantle, and the crust
What causes a volcano to erupt?
The pressure of the earth forms and bubbles up where there is a crack in the Earth (where 2 plates meet).
How does runny lava form a different hill than thick lava?
Runny lava spreads faster making a less steep, short hill. Thick lava spills out slowly causing a steep, high hill.
How does ice wedging happen?
When water freezes it expands inside a rock and cracks it.
What causes a landslide?
Lots of rain and water in one area that is very steep (more than 35')
a rock that comes from deep inside the Earth's core is called a(n):
igneous rock
sedimentary rock
metamorphic rock
igneous rock
Where are our volcanoes located in North America?
Hawaii and Alaska; on the western coast of the US
Name one type of volcano and describe it.
Ash & cinder volcano: steep side, short, small solid fragments of rock and ash
Acid lava cone volcano: erupt slowly, thick lava, cone shape
Shield volcano: very large, gentle sloping sides, thin and runny lava
Composite volcano: very tall, steep, runny lava followed by explosive thick lava and ash
What was underneath the forest on the hill in Central America?
A pyramid of rocks
Why are landslides so dangerous?
They move big heavy things around and can flood areas. The land can go out from under things.
layers of igneous rock that cement together (usually in water) is called a(n):
igneous rock
sedimentary rock
metamorphic rock
sedimentary rock
What is the area called where most of Earth's volcanoes are located?
The Ring of Fire
Which volcano is the most common?
Composite Cone Volcanoes
How are the rocks at the top of a mountain different than the rocks at the bottom of the mountain? Think about how your sugar cube changed from the beginning (top) to the end (bottom)?
Top rocks are more cube-like, bottom rocks are much more round from falling down.
How can you prevent a landslide?
Make hills not so steep.
Build or camp where land is flat.
Monitor how much water you put on your land.
an igneous or sedimentary rock that changes over time from the pressure or extreme heat is called a(n):
igneous rock
sedimentary rock
metamorphic rock
metamorphic rock
They are located where tectonic plates match up and shift.
Describe the difference between felsite and basalt lava and which volcano each comes out of.
Felsite lava is lighter and comes out of cone volcanoes.
Basalt lava is darker and comes out of shield volcanoes.
Will a mountain last forever? Why or not?
No, it will not because over time root wedging and ice wedging will break down the rocks.
Something dangerous that happens in nature...like a flood, a tornado, a landslide, or an earthquake.
What is a geologist?
a scientist who studies rocks