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. spearated into the outer (molten) and inner core (solid)
tectonic plate
The layer of rocks that makes up the outer oart of the earth, including the crust and upper mantle (lithospheric plates)
Continental drift theory
The theory that 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 currents
The process in which the hotter parts of a gas or liquid rise to the top and the coller, denser parts sink.
convergent boundary
When two tectonic plates come together.
mountains
Uplift of crustal plates that form elevated landmass.
volcanoes
A vent of fissure in earth’s surface through which magma and gasses are exploded.
divergent boundary
When tectonic plates split apart.
transform boundary
When tectonic plates slide past each other.
fault
Breaks in the crust. the movement cause seismic waves produce earthquakes.
mid-Ocean ridge
A long fidge of underwater volcanoes between two diverging oceanic plates
Subduction zone
A place where one tectonic plate sinks and melts. Also forms a trench
