In a new Science Advances publication, Assistant Professor James Dottin III demonstrates how Hydrogen may leak from the core into the lowermost mantle, become entrained in mantle plumes, and mix into the upper mantle. "We typically think about the water cycle on the surface," explained Dottin, "but we often don't consider what happens to water beneath our feet through deep Earth processes." By measuring 2H/1H ratios in olivine-hosted basaltic melt inclusions from a Baffin Island lava, Dottin and his team investigated whether mantle plumes contain Hydrogen from the core. "This means that some the the water you're drinking today might be seeing the surface for the first time since the Earth was formed."