Plate Tectonics Flashcards
Crust
The outermost shell of a rocky planet
Mantle
layer of molten 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 (lithospheric plates)
Continental drift theory
The theory that continents gradually drifted over time to their present position.
Asthenosphere
A thin layer of earth, about 150 miles thick, at the border between the mantle and the crust.
Convection current
In which the hotter gasses or liquid rises to the top and the cooler, denser parts sink.
Convergent boundaries
When two tectonic plates come togther.
Mountains
Uplift of crustal plates that form elevated landmasses
Volcanoes
A vent or fissure in the earth in which magma and gasses are expelled
Divergent boundaries
When tectonic plates split apart
Transform Boundary
When tectonic plates slide past or against 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.