Unit 2 Dynamic Earth Vocabulary Flashcards
Pangea
Name given to a supercontinent that began to break apart approximately 200 million years ago.
Continental Drift
Wegner’s hypothesis is that all continents were once connected in a single large landmass that broke apart about 200 million years ago and slowly drifted into position.
Mid-ocean Ridges
Long, narrow mountain range on the ocean floor;
formed by magma at divergent plate boundaries.
Seafloor Spreading
the process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge.
Ocean Trenches
A deep, underwater trough created by one plate subducting under another plate at a convergent plate boundary.
Magma
Molten rock stored below Earth’s surface.
Lava
Lava that erupts onto the Earth’s surface.
Plate Tectonics
Theory that Earth’s surface is broken into large, ridged pieces that move with respect to each other.
Convergent Boundaries
A boundary between two plates that move towards each other.
Divergent Bounderies
A boundary between two plates that move away from each other.
Transformed Bounderies
A boundary between two plates that move past each other.
Subduction
The prosses that occurs when one tectonic plate moves under another tectonic plate.
Fault
A crack or a fracture in Earth’s lithosphere along which movement occurs.
Volcano
A vent in Earth’s crust through which molten rock flows.
Volcanic Arc
a curved line of volcanos that forms a parallel to a plate boundary.