GEO - Chapter 3 Flashcards
What is a side cone on a volcano?
A smaller cone on the side of a volcano, formed by eruptions from a side vent.
What is an ash cloud on a volcano?
A large cloud of ash, gas, and particles ejected into the air during an eruption.
What is the main vent on a volcano?
An internal pathway through which magma rises to the surface.
What is the pyroclastic flow of a volcano?
A fast-moving, hot flow of gas, ash, and volcanic rock fragments.
What is the magma chamber in a volcano?
A reservoir of magma beneath the volcano.
What are volcanic bombs of a volcano?
Large rock fragments ejected from a volcano during an eruption
What is a side vent on a volcano?
An internal side outlet from the main vent of a volcano
Where are the three main places where volcanoes originate?
- Hot spots
- Divergent plate boundaries (rifts and mid-ocean ridges)
- Convergent plate boundaries (subduction zones)
How do volcanoes form
build themselves out of their own expelled debris.
What are the 5 major issues related to volcanic eruptions:
- toxic gases
- lava flows
- pyroclastic flows
- lahars
- volcanic ash release
How do earthquakes occur?
two tectonic plates slip past each other after a build up of pressure + cause a tremor
Where are earthquakes most common?
Transform boundaries (but still occur at converging + diverging boundaries)
Which is faster of P and S waves?
P waves
What movements do P waves travel in?
Push-Pull waves - Forward and Backward
What movements do S waves travel in?
Shakes Side-to-Side
In which order do P and S waves occur?
- P-waves
THEN
- S-waves
What state/s of matter cant P waves travel through?
None - can travel through all!!! (YAYAYAY)
What state/s of matter cant S waves travel through?
Liquids
What did P and S waves help scientists discover about the earth’s interior?
The liquid outer core
What are seismic shadow zones?
- areas on Earth where no waves are detected after an earthquake
- because of how the waves travel through different parts of the Earth.
Why are there no P and S waves detected after an earthquake through seismic shadow zones
- P waves bend when hitting the solid mantle and the liquid outer core boundary - causes shadow zone
- don’t pass through the liquid outer core - shadow zone
What is the amount of degrees beyond which shadow zones are created
104°
What are the causes of tsunamis?
- Underwater Earthquakes
- Underwater Landslides
- Volcanic Eruptions
How do underwater earthquakes cause tsunamis?
when tectonic plates suddenly move - displacing the water and causing the wave
How do underwater landslides cause tsunamis?
large chunk of rock, mud, or sediment falls into the ocean (often triggered by an earthquake), it displaces a lot of water
What 2 volcanic eruption elements cause tsunamis?
- explosion or collapse
- release of steam and gases during the eruption can
both displacing large amounts of water
