| The National Science Foundation plans to sell the research vessel Marcus G. Langseth. Geoscientists are not happy over the loss to their field, as I reported on Monday. The ship is outfitted with state-of-the-art gear, which allows researchers to look deeper into Earth's crust than they would be able to do otherwise. Expeditions on the Langseth have yielded some surprising insights into what lurks below. Take the Langseth's 2011 expedition to Alaska, for instance. What was planned to be a "routine cruise" near the Alaskan coast, as Scientific American reported last summer, revealed a fault that split the seafloor. Two tectonic plates, large sections of Earth's crust that cover the planet like scales on a pangolin, meet 600 miles from Anchorage, in a place called the Shumagin Seismic Gap. There the Pacific plate grinds into the North American plate, cracking the crust into smaller pieces. Tectonic shoving matches between plates can produce earthquakes. The Shumagin Gap, though, hadn't been known to be so active. It was like "a car engine that is properly oiled — the moving parts slide past each other easily, without anything catastrophic happening," wrote Matt Gardine at the University of Alaska Fairbanks. Yet the geology observed by the Langseth, deeper below, revealed that the crust had indeed gunked up. The scientists on the ship, who published their findings in Nature Geoscience in July, concluded that Shumagin Gap contained a structure that was "tsunamigenic" — a fancy way of saying that the fault could give way in a burst of energy and motion to trigger a giant wave. The discovery of the fault "suggests this part of Alaska is particularly prone to tsunami generation," Columbia University seismologist Anne Bécel said in at statement last July. "The possibility that such features are widespread is of global significance." But researchers can't find these features without deep-sea seismology. And, without the Langseth, the techniques available to academic seismologists shrink. What researchers fear more than the loss of the Langseth is that nothing will replace its 235-foot hole in their data. — Ben | 
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