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Images: Plumbing the Plume That Created Samoa

Graduate student Matthew Jackson adjusted a solar-powered seismometer that he positioned on the Samoan island of Tutuila to learn about the composition and structure of Earth's interior. Though located in an idyllic tropical location, his research often required great patience. "I was struggling to get the seismometer working and was taking notes on the 'vital' signs of the instrument," Jackson recalled. "It was hot, the instrument wasn't working, and I just wanted to go to the beach!" (Photo courtesy of Matthew Jackson, Woods Hole Oceanographic Institution)

Island chains such as Samoa and Hawaii are known as hotspots, where magma from the mantle erupts through the crust. This creates seafloor volcanoes that often rise above the ocean surface to form islands. The Samoa chain formed as the overlying crustal plate moves over the stationary injection point of the hotspot. (Illustration by Jayne Doucette, Woods Hole Oceanographic Institution)

Jackson set up seismometers on Samoa to record seismic waves traveling through the Earth beneath the islands. The waves offers clues to the structure and composition of the rocks they travel through. He will compare data from Samoa and Hawaii to explore similarities and differences in the hotspot plumes that formed the two island chains. (Illustration by Jayne Doucette, Wood Hole Oceanographic Institution)

While conducting field work in Samoa, Jackson spoke with local students about his research. The Samoan islands, like Hawaii?s islands, are formed from a plume of hot, buoyant magma that rises from deep within Earth?s mantle and through its crust, erupting to form volcanic islands. Jackson wants to learn more about the similarities and differences in the origins of the island chains. (Photo by Stan Hart, Woods Hole Oceanographic Institution)