Plate Tectonics

Most geologists think that the movement of Earth's plates is caused by

• Earth's magnetic field

• convection currents in the mantle

• earthquakes

• conduction

According to Wegener's hypothesis of continental drift,

• Earth is slowly cooling and shrinking

• Earth's surface is made up of seven major landmasses

• the continents do not move

• the continents were once joined together in a single landmass

Old oceanic crust is more dense than new oceanic crust because it is

• cool

• moving toward a deep-ocean trench

• hot

• closer to the mid-ocean ridge

In sea-floor spreading, molten material rises from the mantle and erupts

• along the edges of all continents

• in deep-ocean trenches

• at the north and south poles

• along mid-ocean ridges

What is Pangaea?

• the name of a German scientist

• the name of an ancient fossil

• another name for continental drift

• the name of the supercontinent that existed millions of years ago

Any trace of an ancient organism that has been preserved in rock is called

• landform

• continent

• landmass

• fossil

What technology did scientists use in the mid-1900s to map the mid-ocean ridge?

• deep sea diving

• satellites

• submarines

• sonar

The geological theory that states that pieces of Earth's lithosphere are in constant, slow motion is the theory of

• sea-floor spreading

• deep-ocean trenches

• subduction

• plate tectonics

A collision between 2 pieces continental crust at a converging boundary produces a

• deep-ocean trench

• mid-ocean ridge

• rift valley

• mountain range

A place where two plates slip past each other, moving in opposite directions, is known as

• transform boundary

• convergent boundary

• divergent boundary

• rift valley