Plates Tectonics Flashcards
Crust
The outermost shell of a rocky planet.
Mantle
Layer of molten rock between the crust and core.
Core
Made of mostly Iron. Separated into the outer core (molten) and inner core (solid).
Tectonic Plate
The layers of rock that makes up the outer part of the earth, including the crust upper mantle (lithospheric plates).
Continental drift theory
The theory continents gradually drifted over time to their present positions.
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 the hotter parts of a gas or liquid rise to the top and cooler, denser parts sink.
Convergent Boundary
When two tectonic plates come together.
Mountains
Uplift of crustal plates that form elevated landmass.
Volcanoes
A vent or fissure in earth’s surface though which magma and gasses are expelled.
Divergent boundary
When tectonic plates split apart.
Transform boundary
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 volcanoes between diverging oceanic plates
Subduction zone
A place where one tectonic plate sinks under another and melts. Also forms a trench.
