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
- In a process taking tens of millions of years, part of the ocean floor sinks back into the mantle at deep-ocean trenches.
2 True/False questions
sea-floor spreading → an undersea mountain chain that is part of a long system of mountains that winds beneath Earth's oceans.
What is the evidence for sea-floor spreading? → Several types of evidence supported the theory of sea floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves.