C2A - Volcanos & Rocks Flashcards
Where is the molten rock from ? How does it get out ?
From the mantle and it emerges through the earths crust
What are volcanos formed by ?
Molten rock
Once magma has risen through the crust what happens ?
It boils over
If the pressure is released suddenly what happens ?
The magma will emerge quite violently
What’s the difference between magma and lava ?
They are the same thing but inside the mantle. It’s called magma. When it erupts it’s called Lava.
There is crust at both the ocean floor and below the continents. Which one is more dense ?
The ocean floor crust
What is subduction ?
When two tectonic plates collide. The dense oceanic plate will be forced under the continental plate.
If oceanic crust is cooler at the edges what result could this have ?
The edges sink easily. Pulling the oceanic plate down.
What happens when the oceanic crust is forced down ?
It melts and starts to rise. If the magma gets to the surface. You have a volcano
Why do geologists study volcanos ?
To see if there are signs of a soon volcanic eruption
What things do scientists use to help the study volcanos ?
Magma movement
What is there more of with the prediction of volcanos than there was in the past ?
Accuracy
Why is it tricky to predict volcanos ?
They are very unpredictable
What are the three different types of rock. And an example ?
Sedimentary - Limestone
Metamorphic - Marble
Igneous - Granite
How is igneous rock formed ?
When molten rock cools down and solidifies
