Wilson thought the hot spot was located in the center of a mantle convection cell where movement was slow. The upper, faster moving part of the convection cell helped carry the Pacific Plate to the northwest.

By the early 1970s, the plate tectonic theory and the presence of hot spots was generally accepted. In 1971, W. Jason Morgan suggested a more important role for hot spots. He proposed that hot spots result from hot, narrow plumes of material that rise from deep within the mantle.

As the hot mantle plume reaches the base of the lithosphere, it spreads laterally. The laterally spreading of the hot mantle helped to move the Earth's rigid outer plates. In all, Morgan proposed 20 different hot spots, some located along mid-ocean ridges and others, like Hawaii and Yellowstone, located within plates.

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