3 Written questions
3 Multiple choice questions
- the process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle
- deep underwater canyons
- a device that bounces sound waves off underwater objects and then records the echoes of these sound waves.
2 True/False questions
What happens at deep-ocean trenches? → deep underwater canyons
mid-ocean ridge → an undersea mountain chain that is part of a long system of mountains that winds beneath Earth's oceans.