Unlike the inner core, this layer of the Earth is liquid because it is under less pressure.
Where is the outer core?
This hypothesis suggests the sea floor is splitting and moving apart, powered by convection currents.
What is sea-floor spreading?
This is the name for the zone where a thin oceanic plate slips below a thicker continental plate.
What is a subduction zone?
This is the primary internal source of Earth's heat, involving elements like Uranium, Thorium, and Plutonium.
What is radioactive decay/nuclear fission?
These distinct, rounded formations are created when magma cools rapidly upon meeting cold ocean water.
What is pillow lava?
Because these plates are lighter and less dense, they do not sink but instead collide to form mountain ranges.
What are continental plates?
This "plastic" layer of the mantle allows the rigid plates of the lithosphere to float and move.
What is the asthenosphere?
Evidence for spreading was found in this "striped" pattern of magnetic variations on either side of a ridge.
What is magnetic striping?
These deep-sea features are formed when the leading edge of a continental plate is dragged downward by a sinking oceanic plate.
What are deep oceanic trenches?
This term refers to the gradual increase in Earth's size during its development from the addition of materials from space.
What is accretion?
Divergent eruptions are less violent because this type of magma contains very little silica.
What is basaltic magma?
These arc-like chains of volcanic peaks are built up on continents above a subducting plate.
What are continental volcanic arcs?
These are the three main types of seismic waves generated by earthquakes, in order of their arrival at a seismograph.
What are P (Primary), S (Secondary), and L (Long) waves?
Evidence for spreading was found in this "striped" pattern of magnetic variations on either side of a ridge.
What is magnetic striping?
This is the approximate lifespan of an oceanic plate from its creation at a ridge to its destruction in a subduction zone.
What is 150-200 million years?