The volcanic activity at Yellowstone National Park in the western United States might be driven by a mantle plume rising from the core-mantle boundary deep in the Earth, reports a study published online this week in Nature Geoscience.
Whether or not a mantle plume - a column of potentially warm, upwelling material - might lie beneath Yellowstone National Park has been hotly debated for decades. Mantle plumes are themselves contentious because seismic images of the Earth’s interior largely failed to unambiguously identify plume-like features that trace all the way down to the deep mantle.
Peter Nelson and Stephen Grand use seismic data collected by EarthScope’s USArray project to image the mantle beneath North America. The authors identify a long, thin, sloping zone within the mantle through which seismic waves travel more slowly - and which may indicate the presence of unusually warm material. The zone extends almost continuously through the mantle, rooted in the core-mantle boundary beneath Mexico and running north-eastwards up to Yellowstone National Park.
This finding implies that the volcanic activity at Yellowstone, which includes hydrothermal springs and explosive geysers like the famous ‘Old Faithful’, as well as super-eruptions in the geologic past, could all ultimately be driven by this deep-mantle plume rising up from above the Earth’s core.