Idea 4 Week 1 -- Continents

Of continental drift, seafloor spreading, and plate tectonics, write the theory that was first used to explain the statement below. Tectonic plates are in constant slow motion on the planet's surface.

plate tectonics

Of continental drift, seafloor spreading, and plate tectonics, write the theory that was first used to explain the statement below. Earth's surface is divided into plates composed of the continents and the seafloor.

plate tectonics

In the 1950s. ____________ mapped the features of the ocean floor.

cartographers

Of continental drift, seafloor spreading, and plate tectonics, write the theory that was first used to explain the statement below. All the continents together formed Pangaea.

continental drift

Seafloor spreading, in fact, is the _________ that causes the tectonic plates to move over the surface of the Earth.

mechanism

Of continental drift, seafloor spreading, and plate tectonics, write the theory that was first used to explain the statement below. New crust is created along mid-ocean ridges.

sea floor spreading

This led a _____(a)_____ named Henry Hess to _____(b)____ that the ocean floor was spreading because ___(c)_____ seeped out of the _____(d)_______ in mid ocean ridges.

(a) geologist (b) hypothesize (c) magma (d) rifts

As lave poured over the ridges and cooled, previously formed rock was pushed across the ocean floor, until it finally sank into a ___________.

trench