science flash cards
Name given to a super-continent that began to break apart approximately 200 million years ago.
Pangaea
Wegeners hypothesis that all continents were once connected in a single large landmass that broke apart about 200 million years ago and drifted slowly to their current positions.
continental drift
Long, narrow mountain range on the ocean floor; formed by magma at divergent plate boundaries.
mid-ocean ridges
A deep underwater trough created by one plate sub-ducting under another plate at convergent plate boundary.
Ocean trenches
Molten rock stored below Earth’s surface
Magma
Magma that erupts onto Earth’s surface
Lava
The process by which new oceanic crusts form along a mid-ocean ridge and older oceanic crusts move away from the ridge.
Seafloor spreading
theory that Earths surface is broken into large, rigid pieces that move with respect to each other.
plate tectonics
The boundary between two plates that move toward each other.
convergent boundary
The boundary between two plates that move away from each other.
divergent boundary
The boundary between two plates that slide past each other.
transform boundaries
The process that occurs when one tectonic plate moves under another tectonic plate.
subduction
A crack or a fracture in Earths lithosphere along which movement to occurs.
fault
A vent in Earth’s crust through which molten rock flows.
volcano
A curved line of volcanoes that forms parallel to a plate boundary
volcanic arc