Geology- Chaper 17.3 and 17.4 Theory of Plate Tectonics and Causes of Plate Motion

rift valley

Long, narrow depression that forms when continental crust begins to separate at a divergent boundary.

divergent boundary

Place where two of Earth's tectonic plates are moving apart; is associated with volcanism, earthquakes, and high heat flow, and if found primarily on the seafloor.

convergent boundary

place where two of Earth's tectonic plates are moving toward's each other; is associated with trenches, island arcs, and folded mountains.

transform boundary

place where two tectonic plates slide horizontally past each other that is characterized by long faults and shallow earthquakes.

subduction

process by which one tectonic plate slips beneath another tectonic plate

theory of plate tectonics

states that Eearth's crust and upper mantle are broken into plates, which are huge rock slabs that move in different directions and at different rates over the Earth's surface

slab pull

tectonic process associated with convection currents in Earth's mantle that occurs as the weight of the subducting plate pulls the trailing lithosphere into a subduction zone.

ridge push

tectonic process associated with convection currents in the Earth's mantle that occurs when the weight of an elevated ridge pushes an oceanic plate toward a subduction zone.