New View of Rainier’s Volcanic Plumbing – EGI’s Phil Wannamaker

We are excited to congratulate EGI Research Professor Phil Wannamaker on the release of his newly published study in the journal Nature.  The article, titled “Pathway from subducting slab to surface for melt and fluids beneath Mount Rainier” is in the current issue of the journal, available today, July 17, 2014. The study, which Phil conceived and co-authored, represents a significant contribution to understanding some of the volcanic and structural characteristics that underlay a Cascades volcanic system– in particular how and where melt and fluids make their way up to Rainier’s magma chamber.  The study makes use of both seismic imaging and magnetotelluric measurements to show how electrical and magnetic fields in the ground vary due to differences in how much underground rock and fluids conduct or resist electricity. The resulting cross-section view is the most detailed image yet, providing new information about the accumulation of partly-molten magma before eruption.

“This is the most direct image yet capturing the melting process that feeds magma into a crustal reservoir that eventually is tapped for eruptions,” says Phil. “But it does not provide any information on the timing of future eruptions from Mount Rainier or other Cascade Range volcanoes.”

The new study and Nature article are great examples of the high-value, cutting-edge science being conducted by EGI scientists in Utah and across the globe.

Phil holds a Ph.D in Electromagnetic Geophysics from the University of Utah and a B.Sc. in Engineering Geology from Queen’s University at Kingston, Canada. He has been active in basic and applied geophysical research for 30 years and joined EGI in 1995 through its merger with UURI. He has lead international teams of investigators in large research projects in U.S. Cascadia, Basin and Range, Southern Appalachia, New Zealand, and Antarctica.

He is an active member of the AGU, GRC, GSA, SEG, and ASEG. In 2011 he was elected a Fellow of the Geological Society of America. He is Trustee and Treasurer for the Gerald W. Hohmann Memorial Trust for Teaching and Research in Applied Electrical Methods. Phil has published 50+ papers and has advised 23 graduate student theses. He has served as associate editor for several journals and as co-editor of a book on EM modeling and inversion.

For more information about the article or Phil’s work at EGI, visit his detailed biographical page on our website.  Phil can also be reached at or (801) 581-3547.

You may view the full article from the University of Utah News  Center here.