plate tectonics Flashcards
Crust
The outermost shell of a rocky planet
Mantle
Layer of molten rock between the crust and core.
Core
Made up of mostly Iron. Separated into the outer coremolten and inner core solid.
Tectonic Plates
The layer of rock that makes up the outer part of the Earth including the crust and upper mantle
(lithospheric plates).
Continental Drift Theory
The theory that continents gradullay drifted over time to their present postions.
Asthenosphere
A thin layer of earth about 150 miles thick at the border between the mantle and the crust.
Convection Current
The process in which in the hotter parts of a gas or liquid rise to the top and the coller denser parts sink.
Convergent Boundry
When two tectonics plates come together.
Mountains
Uplift of crust plates that form elevated landmass.
Volcanos
A vent or fissure in earths surface through which magma and gases are exploded.
Divergant Boundry
When tectonic plates split apart.
Transform Boundry
When tectonic plates slide past each other.
Fault
Breaks in the crust. The movement causes seismic waves which produces earthquakes.
Mid-Ocean Ridge
A long ridge of underwater volcanos between two diverging oceanic plates.
Subduction Zone
A place where one tectonic plate sinks under another and elts. Also forms a trench.
