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 core (molten) and inner core (solid)
Tectonic Plate
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 the 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 rise to the t0p and the cooler, denser parts sink
Convergent boundary
When two tectonic plates come toghether
Mountains
Uplift of a crustal plates that form elevated landmasses.
Volcanoes
A vent or fissure in Earth’s surface through which magma and gases are expelled
Divergent Boundaries
When tectonic plates split apart
Transform Boundaries
When tectonics 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 two diverging oceanic plates.
Subduction Zone
A place where one tectonic plate sinks under another and melts. Also forms a trench
