Earthquake
Where seismic waves originate and rocks first move along the fault
Focus of an earthquake
What is tiny particles of volcanic rock or glass?
Volcanic Ash
Two plates pushing together until one falls down
Reverse fault
What is more dense? Oceanic Crust or Continental Crust?
Oceanic Crust
Name the layers of Earth from the inside to the out
Inner core, Outer core, Mantle, Crust
What is location on earths surface directly above an earthquakes focus?
Epicenter
The opening at the top of the Volcano
Crater
Plate boundaries that move horizontally past each other
Strike-slip
What is a divergent boundary?
Tectonic plates moving away from each other
What causes tectonic plates to move?
Convection Currents
The idea that the earth's crust is made up of moving plates
Theory of Plate Tectonics
Magma that breaks through to the surface is called what?
Lava
Type of fault that occurs when the block of rock above
Normal Fault
What geological features do convergent boundaries create.
Mountains - Continental/Continental
Deep Ocean Trenches- Oceanic/Oceanic
Where do volcanoes and earthquakes occur?
Tectonic plate boundaries
Magnitude can be measured by what instrument?
seismograph
Molton rock that pools under the volcano
Magma Chamber
Breaks in the earth's surface along which rock can move
Faults
What geological features does divergent boundaries form?
Ocean and Rift Valleys
What can s-waves move through?
Solid
Cause of Earthquakes
Build-up and release of energy when two surface plates move against each other.
Define active, dormant and extinct volcano
Active: Erupted the last 20 years.
Dormant: Hasn't erupted the last 20 years.
Extinct: Hasn't erupted in 1000's of years
Two types of folds
Anticline & Syncline
What is the subduction zone? How does it occur?
Where the tectonic plates dive back into the mantle, oceanic goes under continental due to being denser.
What is the name of the single landmass that is thought to have existed at one time?
Pangea