Plate Tectonics Flashcards
Asthenosphere
A layer of ‘plastic’ semi solid rock in the lower mantle
Continental drift
The separating of continents by drifting across the oceans
Magnetic striping
Patterns of magnetism trapped in rocks on each side of plate boundaries
Ocean trench
A deep trench In the ocean floor that is much deeper than the rest of the ocean floor
Plate tectonics
The theory that the earths crust is cracked into many large pieces that move on the asthenosphere
Rifting
The process of continents breaking up, subsiding and allowing in the sea
Sea floor spreading
The process of new crust forming at the ocean ridges and spreading outwards
Subduction
Where the crust is sinking down into the earth
Continental crust
The crust that forms the continents
Converting boundaries
Where plates are colliding with each other
Diverging boundaries
Where plates are moving apart from each other in opposite directions
GPS ground station
A receiver and computer that can detect satellite signals and calculate its position on the earths surface
Island arc
A chain of islands formed at the edges of colliding tectonic plates where one plate subducts
Oceanic crust
The crust that forms the ocean floor
Subduction
When oceanic crust collides with continental crust, and the oceanic plate then sinks below the continental one
