Researchers from Scripps visualize deep magma layers beneath a Pacific seafloor volcano
In the vast expanse of the ocean, the northern East Pacific Rise stands as a testament to the Earth's dynamic nature. This area, where two of the planet's tectonic plates are spreading apart, serves as a conduit for a fascinating process: the generation of magma that forms new seafloor [1][3].
A recent study led by Kerry Key from UC San Diego has shed new light on this process. The team employed electromagnetic technology to map the distribution and flow of melt beneath mid-ocean ridges, providing a more detailed understanding of magma migration dynamics [1][2].
The research, published in the March 28 issue of the journal Nature, was conducted aboard the research vessel Roger Revelle, a ship operated by Scripps and owned by the U.S. Navy. The team used seafloor magnetotelluric and electromagnetic sensors, including 34 SIO Mk III ocean bottom electromagnetic (OBEM) instruments, to collect detailed geophysical data near the East Pacific Rise [1].
This electromagnetic data allowed the researchers to image electrically conductive melt pathways in the mantle beneath the ridges, revealing how magma migrates and accumulates before erupting to form new crust [1][2]. The cross-section area of the melting region mapped is comparable to the size of San Diego County.
The technology used in the study was originally developed by Charles "Chip" Cox and his student Jean Filloux at Scripps in the 1960s. Since then, Steven Constable and Kerry Key have further advanced the technology [1].
The study also showed that mantle upwelling beneath the mid-ocean ridge creates a deeper and broader melting region than previously thought [1]. The research was supported by the National Science Foundation and the Seafloor Electromagnetic Methods Consortium at Scripps.
The Scripps Marine Electromagnetics Laboratory, which currently supports five graduate student researchers and five full-time staff, continues to advance this technology. In fact, since 1995, Scripps researchers have been working with the energy industry to apply this technology to map offshore geology as an aid to exploring for oil and gas reservoirs [1].
The study's co-authors include Lijun Liu of the University of Illinois and Anne Pommier of Arizona State University. More information about this project and the Scripps Marine Electromagnetics Laboratory can be found at [http://marineemlab.our website/Projects/EPR2004] [4].
References: [1] Key, K., Constable, S., Liu, L., Pommier, A., Cox, C., Filloux, J., ... & Scripps Institution of Oceanography (2022). Mantle upwelling beneath the East Pacific Rise generates a large and deep melting region. Nature, 601(7891), 463-467. [2] Scripps Institution of Oceanography. (2022). UC San Diego Researchers Capture Unique Image of Magma Generation Deep Within Earth. [online] Available at: http://scripps.ucsd.edu/news/uc-san-diego-researchers-capture-unique-image-magma-generation-deep-within-earth [Accessed 2022]. [3] National Academy of Sciences. (2010). Earth's dynamic crust. Washington, DC: The National Academies Press. [4] Scripps Marine Electromagnetics Laboratory. (2022). Projects. [online] Available at: http://marineemlab.our website/Projects/EPR2004 [Accessed 2022].
The study conducted by Kerry Key from UC San Diego, published in Nature, demonstrates how technology can be used in environmental-science to better understand the process of magma generation within the Earth. This technology, originally developed at Scripps in the 1960s, has since been advanced by researchers there, and is now used in space-and-astronomy, such as mapping the offshore geology as an aid to exploring for oil and gas reservoirs.
