Slices from a 3D image of Okmok Volcano, Alaska, constructed from continuous recordings of ocean noise. Okmok is one of the most active volcanoes in the Aleutian island chain and poses a threat to aviation in the heavily used north Pacific air-traffic corridors. The 3D image is centered on the main axis of the volcano. Independent GPS, InSAR, and petrologic data further support the presence of a shallow magma chamber at Okmok. (Image courtesy of M. Haney.)
Also published: Masterlark, T., M. Haney, H. Dickinson, T. Fournier, and C. Searcy (2010), Rheologic and structural controls on the deformation of Okmok volcano, Alaska: FEMs, InSAR, and ambient noise tomography, J. Geophys. Res., 115, B02409, doi:10.1029/2009JB006324.