Earth Science (EARTH-1141) - Plate Tectonics Vocab

Chapter 4

plate tectonics

explain the observed motion of the earth’s lithosphere through the mechanisms subduction and seafloor spreading which form earth’s major features and causes earthquakes

Divergent Boundary

boundary where plates move apart. causes shallow earthquakes and mid ocean ridges

seafloor spreading

divergent plate boundary produces a long narrow fracture in the ocean floor, hot molten rock from the mantle migrates up to fill the fracture and produce new slivers of seafloor

ocean ridge

newly created oceanic lithosphere is hot/less dense and rises, creating an elevated position on the seafloor

rift valley

long narrow trough that represents a region where divergence is taking place

continental rift

divergent boundaries that form within a continent resulting in an elongated depression where the lithosphere sinks down and may eventually create a new ocean basin

convergent boundary

plate boundary where two plates move together, resulting in the subduction of oceanic crust underneath continental crust or mountain zones in the case of continent-continent convergence

deep ocean trench

elongated depression in sea floor as a result of subduction during convergent plate boundaries

transform boundary

boundary where plates slide past one another