Earth Structures Chapter 3

A rift valley forms at a

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

According to Wegner's hypothesis of continental drift,

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

Describe what is happening at point Z in the diagram.

What feature occurs at Y?

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

A place where 2 plates slip past each other, moving in opposite directions is known as

What is Pangea?

The place where two plates come together is known as

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

What feature occurs at X?

Mid-ocean ridges are

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

 Pieces of Earth's lithosphere are in constant, slow motion is the theory of

The ocean floor sinks beneath a deep-ocean trench and back into the mantle is known as