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Contents of 12.6 What does the mantle-plume hypothesis explain that plate tectonics cannot explain?

• Hot spots are areas of prolific generation of igneous rocks not explained by plate tectonics. Some hot spots occur within plates, while others occur at boundaries.
• Tracks of extinct volcanoes are progressively older at greater distance from active hot-spot volcanoes.
• The plume hypothesis suggests that hot spots mark places where hot mantle convectively rises to the base of the lithosphere from the core-mantle boundary.
• Narrow plume evidence is yet inconclusive. However, most hot spots are located above larger "superplumes" in the lower mantle.

12.6 What does the mantle-plume hypothesis explain that plate tectonics cannot explain?