Chapter 17 Vocab - Plate Tectonics Flashcards
The study and practice of making maps.
Cartographer
A hypothesis that proposed that Earth’s continents had once been joined as a single landmass that broke apart and sent the continents adrift.
Continental Drift
Greek meaning “all the Earth”, a single land mass that began to break apart about two million years ago.
Pangaea
Chain of underwater mountains that run throughout the ocean basins.
Mid-ocean Ridge
A narrow, elongated depression in the sea floor.
Deep-Sea trench
Device used to map the ocean floor that detects small changes in magnetic fields.
Magnetometer
When Earth’s magnetic field changes in polarity between normal and reversed.
Magnetic Reversal
The study of the history of Earth’s magnetic field.
Paleomagnetism
An imaginary line on a map that shows points that have the same age.
Isochron
The theory that explains how new oceanic crust is formed at mid-ocean ridges and destroyed at deep sea trenches.
Sea floor spreading
Huge pieces of crust and rigid upper mantle that fit together at their edges to cover earth’s surface.
Tectonic Plates
Place where two of Earth’s tectonic plates are moving apart.
Divergent Boundary
Long, narrow depression that forms when continental crust begins to separate at a divergent boundary.
Rift Valley
Place where two of Earth’s tectonic plates are moving toward each other.
Convergent Boundary
Process by which one tectonic plate slips beneath another tectonic plate.
Subduction
A region where two tectonic plates slide horizontally past each other.
Transform Boundary
Tectonic process associated with convection currents in Earth’s mantle that occurs when the weight of an elevated ridge pushes an oceanic plate toward a subduction zone.
Ridge Push
Tectonic process associated with convection currents in Earth’s mantle that occurs as the weight of the subducting plate pulls the trailing plate into a subduction zone.
Slab Pull
