Mapping and sampling of a portion of the mid-Atlantic spreading center, where a unique geochemical signature was determined for a 1980's 'popping rock' sample, will take advantage of recent recognition that tectonic deformation may play a role in focusing volatile fluxing from the mantle. Geophysical mapping, targeted sampling by ROV, and a complete suite of post-cruise geochemical analyses aim to determine whether the early quantification of mantle volatiles was representative for the region and/or whether such signatures cluster only near faults, thus implying localized fluxing. Such finding could uproot long-standing inferences about background mantle volatile contents. Students will be introduced to marine research and a postdoc will delve into a new aspect of spreading center processes. Collaboration with IPGP France will train these young scientists in integrated, international, interdisciplinary geoscience.