Sea Floor Spreading

What is a mid ocean ridge?

• Rocks shaped like pillows.

• The process by which molten material adds new oceanic crust to the ocean floor.

• A deep valley or canyon along the ocean floor beneath which oceanic crust slowly sinks towards the mantle.

• An undersea mountain chain where new ocean floor is produced.

What is a deep ocean trench?

• A deep valley or canyon along the ocean floor beneath which oceanic crust slowly sinks toward the mantle.

• The process by which oceanic crust sinks beneath a deep ocean trench and back into the mantle at a convergent plate boundary.

• An undersea mountain chain where new ocean floor is produced.

• The process by which molten material adds new oceanic crust to the ocean floor.

What is subduction?

• A device that scientists use to map the ocean floor.

• The process by which oceanic crust sinks beneath a deep ocean trench and back into the mantle at a convergent plate boundary.

• A chain of underwater mountains along which sea floor spreading occurs.

What is sonar?

• The process by which the ocean floor sinks into the mantle.

• The process that continually adds new material to the ocean floor.

• A generated sun ray.

• A device that scientists use to map the ocean floor.

What happens to old oceanic crust as new molten material rises from the mantle?

• The molten material spreads out, pushing older rock to both sides of the ridge.

• It sinks down due to density.

• It gets evaporated.

• The Earth's ocean floors move like conveyor belts, carrying the continents along with them, as they move.

The Pacific Ocean is expanding.

• True

• False

What is evidence of sea floor spreading?

• Continental deflection

• Radiation, conduction, convection

• Rocks shaped like pillows in central valley of mid ocean ridges, Magnetic materials in rocks line up in direction of Earth's magnetic poles, Evidence from drilling samples (Older rocks found as you move away from mid ocean trenches)(The young rocks at the center of the trenches)

• Oceanic crust

the Atlantic Ocean is expanding.

• False

• True

The Earth's ocean floors move like....

• Coriolis Effect.

• Elevators.

• Sun rays.

• Conveyor belts.

This process called________continually adds new material to the ocean floor.

• Subduction.

• Pillow rocks.

• Sea floor spreading.

• Oceanic crust