Environmental Studies, The Blue Planet, Chapter 5

Abyssal Plain
Large flat areas on the sea floor. They form from mud and debris settling on the sea floor.
Continental Collision Zone
Marks the final disappearance of an ocean basin between converging continents. Results in crumpling and mountain ranges.
Continental Drift
When the supercontinents become the modern regular continents and, well, drift. (Alfred Wegener)
Continental Rise
A region where the sea floor flattens and continental crust meets oceanic crust.

Continental Shelf
The flooded part of a continent.
Continental Shield
An assemblage of cratons and orogens.
Continental Slope
The drop-off at the seaward edge of the continental shelf
Divergent Plate Margin
Fractures in the lithosphere where two plates move apart.
A stable core of very ancient rock (continental crust).
Convergent Plate Margin
Where two plates move towards each other.
The solid earth.
Gravity Anomaly
Difference of gravity between different points on Earth.
The property whereby the lithosphere maintains a floatational balance as it ride the asthenosphere like a surfboard.

Magnetic Field
The magnetic field generated by the outer core, surrounding the Earth. Caused by electrical energy from friction in the inner core.
Magnetic Reversal
When the north and south poles reverse. See also: Polar Wandering.
Oceanic Trench
The place where the ocean-capped lithosphere sings into the asthenosphere.
A type of continental crust which are elongate and have been bent and fractured in continental collisions.

The magnetism locked in ancient minerals.
The study of the movement of the lithosphereic plates.
Plate Tectonics
The branch of tectonics that deals with the /interactions/ of the lithospheric plates.
The north-south directionality of the Earth’s magnetic field.

Pole Wandering
The poles don’t wander, the continents wander, making it seem like they do.
The result of the cycle of spreading. Also a popular MMORPG.
Seafloor Spreading
The result of ocean crusts moving and being pushed apart by lava.

As it grows, it has alternating magnetic bands.

Spreading Center
Another term for divergent plate margins.
Transform Plate Margins
Fractures in the lithosphere where two plates slide past each other.
The horizontal or sliding motion of transform plate margins.
When slabs of lithosphere (capped by oceanic crust) sinks into the mantle.
Subduction Zone
The point at
Subduction Zone
Where subduction happens.
Large continental complexes.