Structure of the Earth and Plate Tectonics

Front

What do tectonic plates float on?

Back

Tectonic plates float on the asthenosphere.

Front

True or False: Alfred Wegener showed that the sea floor was spreading and moved the continents.

Back

False

Front

True or False: Sea-floor Spreading adds new material to the ocean floor?

Back

True

Front

Who proposed that the ocean floor was expanding around mid ocean ridges?

Back

Harry Hess.

Front

Is continental crust more dense than oceanic crust?

Back

False. Continental crust is less dense than oceanic crust.

Front

What is the lithosphere?

Back

The lithosphere is the rigid outer layer of the Earth, consisting of the crust and upper mantle.

Front

What is the asthenosphere?

Back

The asthenosphere is the semi-fluid layer of the mantle beneath the lithosphere, allowing tectonic plates to move.

Front

What is sea-floor spreading?

Back

Sea-floor spreading is the process by which new oceanic crust is created at mid-ocean ridges as tectonic plates move apart.

Front

What evidence supports the theory of plate tectonics?

Back

Evidence includes the fit of continental coastlines, fossil distribution, and geological similarities across continents.

Front

What are the three types of plate boundaries?

Back

The three types of plate boundaries are divergent, convergent, and transform boundaries.