Investigating water-rock interactions in crust beneath the seafloor using the triple oxygen-isotope approach

The National Science Foundation Division of Ocean Sciences awarded Western Michigan University $222,575 under the Geosciences program (CFDA 47.050) on September 15, 2026, to investigate water-rock interactions in oceanic crust using triple oxygen-isotope analysis.

The project applies the triple oxygen-isotope method to mineral separates from scientific ocean drilling samples, including pillow basalts, sheeted dikes, and hydrated upper mantle, to constrain temperature, water volume, and fluid composition during seawater-rock interaction beneath the seafloor. The work will resolve the composition of fluids circulating at various depths within the oceanic crust and estimate seawater isotope composition at the time of alteration and its variation through geologic time. Results will inform understanding of oceanic crust alteration, evolution, and seafloor ore deposit origins.

The award supports an early-career principal investigator, graduate and undergraduate student research opportunities, and laboratory development at Western Michigan University in Kalamazoo, Michigan. The recipient will establish a new laboratory available for course-based research and collaborations with nearby universities, and will develop an open reference page for scientific ocean drilling hole 504B, one of the deepest drill holes in oceanic crust. The period of performance extends from the award date through August 31, 2029. No sub-awards are planned.

Abstract

The entire ocean volume circulates through the oceanic crust beneath the seafloor about every one million years. This project will use a new technique to study the interactions between water and rocks during this process. The triple oxygen-isotope method simultaneously provides constraints on temperature, water volume, and fluid composition. The analyses will resolve, for the first time, the composition of fluids circulating at various depths beneath the seafloor. The results are important for understanding alteration and evolution of oceanic crust and seafloor ORE deposit origins. The project will support an early career principal investigator, provide research opportunities for graduate and undergraduate students, and support a laboratory at a regional, student-centered university. This study will apply the triple oxygen-isotope approach to mineral separates from a comprehensive suite of oceanic lithologies. The scientific ocean drilling samples include pillow basalts, sheeted dikes, and hydrated upper mantle. The results will be used to estimate the seawater isotope composition at the time of alteration and how IT could have varied through geologic time. The project will support a new laboratory that will be available for use in course-based research projects and for collaborations with scientists at nearby universities; IT will also develop an open reference page for scientific ocean drilling hole 504B, one of the deepest drill holes in oceanic crust. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.- subawards are not planned for this award.