Sea-Floor Spreading Review

Sea-floor spreading is the process by which the ocean floor sinks back into the mantle.

When scientists drilled for rock samples, they found that the closer rock is to the mid-ocean ridge the younger it is

Sea-Floor spreading is a process by which new crust is added to the ocean floor.

The part of the ocean floor where subduction occurs

Sonar is a device that uses sound waves to measure the distance to an object

Long chains of mountains that rise up from the ocean floor

When scientists drilled for rock samples, they found that the farther rock is from the mid-ocean ridge the older it is

Newly formed crust is

Older crust is

This is a piece of evidence that scientists use to support sea-floor spreading.

the longest mountain ranges on Earth