Earth Systems: Unit 04 Vocabulary (Plate Tectonics & Continental Drift)

Vocabulary flashcards covering key terms related to plate tectonics and continental drift.

Continental Drift

The change in position of continents over time.

Continental Rift Zone

A region within a continent where continental crust begins to thin and split apart.

Divergent Plate Boundary

A boundary where tectonic plates move away from each other.

Subduction Zone

The boundary between plates where subduction occurs.

Trench

The deep ocean trough formed when one plate subducts beneath another.

Volcanic Island Arc

A chain of volcanic islands formed when one oceanic plate subducts beneath another oceanic plate.

Transform Plate Boundary

A plate boundary where plates slide past each other without new lithosphere being created, or old lithosphere being destroyed.

Rift Valley

The valley formed when a continent begins to split apart.

Hotspot

A region where volcanoes form when lithosphere is heated from beneath by a plume of hot mantle.

Mid-Ocean Ridge/SeaTloor Spreading Center

Volcanic ridges in oceans where new ocean crust is formed.

Wilson Cycle

The cycle of continental rifting, the formation of a new ocean basin as rifting advances, followed by the closure of the ocean basin as plates collide.

Apparent Polar Wandering

The inaccurate impression from paleomagnetic data that the magnetic North Pole has wandered widely over Earth's surface, assuming the continents have remained fixed.

SeaFloor Magnetic Stripes

Alternating zones of high and low magnetic fields in rocks on the ocean floor reflecting changes in Earth's magnetic field in the past.

Subduction

The process of oceanic crust moving beneath another tectonic plate and into the mantle.

Continental Volcanic Arc

A chain of volcanoes found on continental plate margins that are located along subduction zones.

Supercontinent

A single large continent formed when all continents merge.

Convergent Plate Margin

A boundary where tectonic plates collide.

Slab Pull

Tectonic plate movement mechanism resulting from dense plate margins falling into the interior of the Earth along subduction zones.

Ridge Push

Tectonic plate movement mechanism resulting from rocks falling away from elevated mid-ocean ridges.

Pangea

A supercontinent existing from approximately 335 million years ago to 175 million years ago.