Plate Tectonics Vocabulary

Continental Drift

• the gradual movement of the continents slowly moving across the surface of Earth

Pangaea

• hypothetical continent that included all of the current land (then formed together) that makes up earth now

Plate Tectonics

• the theory explaining the movement of earth's crust that moves slowly over the mantle (inner part of the earth)

Plate

• a formation of the earth that has broken off and is slowly shifting away from the other portions of land that make up the earth's crust

Divergent Boundary

• the area that exists between tectonic plates that are moving away from one another

Convergent Boundary

• (also known as destructive plate boundary) is an actively deforming region in which 2 or more plates move towards each other and collide

Transform Fault Boundary

• (also known as conservative plate boundary) these faults don't create or destroy the lithosphere, its goes horizontal in either direction

Oceanic Ridge

• an elevated region with a valley on the ocean floor at the boundary between two tectonic plates

Rift Valley

• a large depression in the earth with steep walls formed by the displacement of the earth by fault systems

Seafloor Spreading

• the formation of new areas in the oceanic crust which happens by magma erupting through the surface and the movement that happens on either side

Subduction Zone

• The boundaries of a subduction zone mark the collision between two of the earth's tectonic plates. The plates are pieces of the earth's crust that slowly move across the planet's surface over millions of years.

Trench

• a long steep depression in the earth caused by the weathering and erosion of water and wind

Volcanic Island Arc

• a usually curved mass of volcanoes bound together by an oceanic trench

Paleomagnetism

• the study of geophysics concerned with the magnetism in rocks that is controlled by the earth's magnetic field

Hot Spot

• volcanic regions thought to be fed by parts of the earth's mantle that are very hot

Convection

• the movement caused in a fluid by the actions of hotter (less dense) material to rise, and colder (more dense) materials to sink by gravity which results in heat transfer

Slab-Pull

• Slab pull is the motion of a tectonic plate that can be accounted for by its subduction. Plate motion is partly driven by the weight of cold and dense plates sinking into the mantle at trenches.

Ridge-Push

• Ridge push is a proposed mechanism for motion in plate tectonics. Because mid-ocean ridges have a higher elevation than the rest of the ocean floor, gravity causes the ridge to push on the lithosphere that is farther from the ridge.

Aesthenosphere

• the upper layer of the earth's mantle (below the lithosphere) in which convection is thought to occur.

Mantle

• The region of the inside of the earth between the core and the crust . The mantle is more than two thousand miles thick and makes up more than three-quarters of the volume of the earth.