Geology and Atmospheric Science Flashcards

Front

Asthenosphere

Back

The soft, flexible upper layer of the mantle, on which the tectonic plates move.

Front

Continental Drift

Back

The theory that all of Earth’s continents were once joined together into a single large landmass, and then moved apart, forming the continents we see today.

Front

Convection

Back

Transfer of heat by movement of a fluid.

Front

Convection Currents

Back

Movement within hot fluids, when the heat source is on the bottom, such as in a boiling pot of soup on the stove. Convection currents happen because the hotter material is less dense and rises; when it reaches the surface, it cools and becomes less dense, so it sinks. This rising and sinking creates a circular motion within the fluid.

Front

Convergent Plate Boundaries

Back

Where two tectonic plates move toward each other.

Front

Divergent Plate Boundaries

Back

Where two tectonic plates move away from each other.

Front

Gondwana

Back

The southern continent formed when Pangaea split into two pieces.

Front

Laurasia

Back

The northern continent formed when Pangaea split into two pieces.

Front

Lithosphere

Back

The rigid, brittle layer made up of the crust and the uppermost part of the mantle. It is broken up into pieces called tectonic plates.

Front

Mantle Convection

Back

Convection currents in the mantle that occur because hot rock in the lower part of the mantle is less dense and rises, and cooler rock in the upper part of the mantle cools, becomes more dense, and sinks. Mantle convection is thought to be the mechanism driving the movement of tectonic plates.