plate tectonics Flashcards
crust
The outermost shell of a rock planet.
mantile
layer of molten rock between the crust 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 lihospheric plates
continental drift theory
the theory that continetns 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 prcess in which the hotter parts of a gas or iquid rise to the top and the cooler, denser parts sink.
convergent boundary
when two tectonic plates come togethor.
mountains
up lift crustal playes that form elevated landmasses
volcanoes
a vent of rissure in earth surface through which magma and gases are expelled
Divnergent bundary
when teectonic plates split apart divergebt boundary
transform boundary
when tectonic plates slide past each other
fault
Breaks in the crust. The movement causes seismmic wakes which produces earthquakes.
Mid- Ocean Ridge
A long ridge of underwter olcanoes between two diverging oceanic plates.
Subduction Zone
A place where one tectonic plates sinks under another and melts. Also forms a trench.
