Chapter 4: Plate Tectonics

Vocabulary flashcards based on key concepts in Plate Tectonics.

Plate Tectonics

The theory explaining the structure and movement of the Earth's lithosphere, which is broken into tectonic plates.

Lithosphere

The rigid outer layer of the Earth, composed of the crust and the upper mantle.

Asthenosphere

The highly viscous layer of the upper mantle that lies below the lithosphere and allows for tectonic plate movement.

Subduction Zone

A region where one tectonic plate moves under another and sinks into the mantle.

Continental Drift

The hypothesis that continents move across the Earth's surface over geological time.

Divergent Boundary

A tectonic plate boundary where two plates are moving away from each other, often associated with seafloor spreading.

Convergent Boundary

A tectonic plate boundary where two plates move towards each other, often forming mountains or subduction zones.

Transform Fault

A strike-slip boundary where two plates slide past each other horizontally.

Eustatic Change

A global change in sea level caused by variations in the volume of water in the oceans.

Isostatic Change

Local changes in sea level due to the vertical movement of land masses.

Hot Spots

Locations on the Earth's surface that are directly above plumes of hot magma from the mantle.

Paleomagnetism

The study of the record of the Earth's magnetic field in rocks, sediment, or archeological materials.

Rift Zones

Areas where tectonic plates are moving apart and creating new oceanic crust.

Mid-ocean Ridge

An underwater mountain range formed by plate tectonics, where new ocean floor is created.

Seafloor Spreading

The process by which new oceanic crust is formed at mid-ocean ridges and slowly moves away from the ridge.

Bathymetry

The study of underwater depth of ocean floors or lake floors.

Volcanic Arc

A chain of volcanoes formed above a subducting plate, creating islands or coastal mountains.