Seafloor spreading

Front

Where are the youngest rocks on the ocean floor located?

Back

at mid-ocean ridges

Front

The crust and upper mantle make up Earth's ____.

Back

lithosphere

Front

Scientists have observed that the continents move apart or come together at speeds of a few centimeters per ____.

Back

year

Front

Seafloor spreading occurs because ____.

Back

molten material beneath Earth's crust rises to the surface

Front

A vast, underwater mountain chain is called a(n) _________.

Back

ocean ridge

Front

What particular event is shown on the picture?

Back

subduction zone

Front

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

Back

sonar

Front

In sea-floor spreading, where does molten material rise from the mantle and erupt?

Back

along mid-ocean ridges

Front

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

Back

subduction

Front

The process of ___________ continually adds new crust to the ocean floor along both sides of the mid-ocean ridge.

Back

seafloor spreading