Most divergent boundaries are found here.
On the seafloor
The majority of volcanoes on Earth are found here.
The Ring of Fire
This is what happens to a rock that undergoes elastic deformation once the stress has been removed.
It returns to its original shape.
This is the movement which occurs in the asthenosphere and is driven by the radioactive decay of elements deep within the Earth. The force which moves the plates.
What are convection currents.
This is the type of boundary where the plates slide past each other.
What is transform boundary.
This landform results from the divergence of continental crust.
What is a rift valley. Ex: Iceland
At Earth´s surface, lava is released through these openings.
What are vents.
This is the type of wave that causes rock to move both up and down and side to side.
What is a surface wave.
The Hawaiian Islands were formed by this type of geologic features.
What is a hot spot.
Oceanic crust is made of mostly this type of rock.
What is basalt.
This is the process by which new oceanic crust forms at ocean ridges and slowly moves away from the spreading center until it is subducted and recycled at deep-sea trenches.
Sea floor spreading
This type of volcano would have lava with low viscosity.
What is a shield volcano.
A shield volcano is a nonexplosive volcano with runny lava.
These waves are the first to arrive at a seismic station.
Primary waves or P waves
This type of volcano is generally small and explosive.
What is a cinder cone volcano.
These are characteristics of transform boundaries.
Long faults & shallow earthquakes
Wegener based his theory of continental drift on these three main pieces of evidence.
Animal fossils
Climate fossils (plant fossils in Antarctica)
Rock features
This composite volcano erupted in Washington State in 1980.
Mt. St. Helens
Composite volcanoes alternate between explosive and quiet eruptions.
This is the numerical scale used to describe an earthquake magnitude.
These are rock fragments and particles ejected by a volcanic eruption. Can vary in size from ash to large boulders.
What is tephra.
Continental crust is mostly made up of this type of rock.
Granitic rocks, which are less dense than basalt.
This is the small plate that is located off the Northwest coast of the United States. It is currently subducting under the North American plate.
What is the Juan de Fuca Plate
These two factors determine how explosive a volcano will be.
silica and water content
This is the point on the Earth that is directly above the focus of an earthquake.
What is the epicenter.
These are characteristics of convergent boundaries.
This happens when the flow in the outer core changes, and Earth’s magnetic field changes direction.
Magnetic reversal