iMUSH was a four year collaborative research project involving several institutions and supported by the GeoPRISMS and EarthScope Programs of the US National Science Foundation to illuminate the architecture of the greater Mount St. Helens magmatic system from slab to surface.
About the iMUSH project
iMUSH was a four year collaborative research project involving several institutions and supported by the GeoPRISMS and EarthScope Programs of the US National Science Foundation to illuminate the architecture of the greater Mount St. Helens magmatic system from slab to surface.
To determine the architecture of magmatic systems in general, including the extent and characteristics of highly crystalline magma bodies, and to resolve major tectonic controls on volcanism along the Cascade arc, a variety of geophysical imaging techniques such as magnetotelluric, high-resolution active source seismic imaging and passive seismic monitoring and imaging, integrated with geochemical-petrological data, were used to image and interpret the crust and upper mantle in the greater Mount St. Helens area.

Left: Map of the active source deployment. In the summer of 2014, 23 shots were recorded by about 2500 Texan seismometers installed in two deployments, in addition to 950 Nodal seismometers. The black line shows the location of cross-sections in Figure 2. Right: Locations of permanent and temporary broadband seismometers used in the passive source experiment, magnetotelluric sites, and petrologic samples.
Participant list
Eight Principal Investigators (PIs) from six different institutions were collaborating on the iMUSH project. In addition to these NSF funded investigators, five Investigators from the three US Geological Survey research groups were closely involved with several parts of the project.
- Geoffrey A Abers (Cornell University)
- Olivier Bachmann (ETH-Zurich)
- Paul Bedrosian (USGS)
- Dawnika L Blatter (USGS)
- Esteban Bowles-Martinez (Oregon State University)
- Michael A Clynne (USGS)
- Kenneth C Creager (University of Washington)
- Kayla Crosbie (Cornell University)
- Roger P Denlinger (USGS)
- Margaret E Glasgow (University of New Mexico)
- Jiangang Han (University of Washington)
- Steven M Hansen (University of New Mexico)
- Graham J Hill University of Canterbury
- Eric Kiser (University of Arizona)
- Alan Levander (Rice University)
- Michael Mann (Cornell University)
- Xiaofeng Meng (University of Washington)
- Seth C Moran (USGS)
- Jared Peacock (USGS)
- Brandon Schmandt (University of New Mexico)
- Adam Schultz (Oregon State University)
- Thomas W Sisson (USGS)
- Roque A Soto Castaneda (Cornell University)
- Weston A Thelen (USGS)
- Carl W Ulberg (University of Washington)
- John E Vidale (University of Washington)
- Maren Wanke (ETH-Zurich)
iMUSH is funded by NSF-GeoPRISMS, NSF-Earthscope with substantial in-kind support from the USGS.
Visit the iMUSH website for more information about the project.
Ulberg, C.W., K.C. Creager, S.C. Moran, G.A. Abers, A. Levander, E. Kiser, B. Schmandt, S. Hansen, R. Crosson, 2020. Local source Vp and Vs tomography in the Mount St Helens region with the iMUSH broadband array. Geochemistry, Geophysics, Geosystems, 21, e2019GC00888. doi: 10.1029/2019GC008888
Crosbie, K.J., G.A. Abers, M.E. Mann, H.A. Janiszewski, K.C. Creager, C. Ulberg, S. Moran, 2019. Shear velocity structure from ambient noise and teleseismic surface wave tomography in the Cascades around Mount St. Helens. Journal of Geophysical Research, v. in press. https://doi.org/10.1029/2019JB017836
Eakin, C.M., E.A. Wirth, A. Wallace, C.W. Ulberg, K.C. Creager, G.A. Abers, 2019. SKS splitting beneath Mount St. Helens: Constraints on subslab mantle entrainment. Geochemistry, Geophysics, Geosystems, 20, 4202–4217. https://doi.org/10.1029/2019GC008433
Kiser, E., A. Levander, C. Zelt, B. Schmandt, S. Hansen, 2019. Upper crustal structure and magmatism in southwest Washington: Vp, Vs, and Vp/Vs results from the iMUSH active-source seismic experiment. Journal of Geophysical Research: Solid Earth, 124(7), 7067-7080. https://doi.org/10.1029/2018JB016203
Mann, M.E., G.A. Abers, K.J. Crosbie, K.C. Creager, C. Ulberg, S. Moran, S. Rondenay, 2019. Imaging subduction beneath Mount St. Helens: Implications for slab dehydration and magma transport. Geophysical Research Letters, 46, 3163–3171, https://doi.org/10.1029/2018GL081471
Wanke, M., M.A. Clynne, A. von Quadt, T.W. Vennemann, O. Bachmann, 2019. Geochemical and petrological diversity of mafic magmas from Mount St. Helens. Contributions to Mineralogy and Petrology, 174, 10. https://doi.org/10.1007/s00410-018-1544-4
Wanke, M., O. Karakas, O. Bachmann, 2019. The genesis of arc dacites: The case of Mount St. Helens, WA. Contributions to Mineralogy and Petrology, 174, 7. https://doi.org/10.1007/s00410-018-1542-6
Bedrosian, P.A., J.R. Peacock, E. Bowles-Martinez, A. Schultz, G.J. Hill, 2018. Crustal inheritance and a top-down control on arc magmatism at Mount St. Helens: Nature Geoscience, 11, 865–870. https://doi.org/10.1038/s41561-018-0217-2
Glasgow, M.E., B. Schmandt, S.M. Hansen, 2018. Upper crustal low-frequency seismicity at Mount St. Helens detected with a dense geophone array. Journal of Volcanology and Geothermal Research, 358, 329–341. https://doi.org/10.1016/j.jvolgeores.2018.06.006
Han, J., J.E. Vidale, H. Houston, D.A. Schmidt, K.C. Creager, 2018. Deep long‐period earthquakes beneath Mount St. Helens: Their relationship to tidal stress, episodic tremor and slip, and regular earthquakes. Geophysical Research Letters, 45, 2241–2247. https://doi.org/10.1002/2018GL077063
Kiser, E., A. Levander, C. Zelt, B. Schmandt, S. Hansen, 2018. Focusing of melt near the top of the Mount St. Helens (USA) magma reservoir and its relationship to major volcanic eruptions. Geology, 46, 775–778. https://doi.org/10.1130/G45140.1
Blatter, D.L., T.W. Sisson, W.B. Hankins, 2017. Voluminous arc dacites as amphibole reaction-boundary liquids. Contributions to Mineralogy and Petrology, 172, doi:10.1007/s00410-017-1340-6
Olson, S., 2017. The Next Big Bang. Scientific American, 317(5), 34-41 10.1038/scientificamerican1117-34
Wang, Y., F. Lin, B. Schmandt, J. Farrell, 2017. Ambient noise tomography across Mount St. Helens using a dense seismic array. Journal of Geophysical Research: Solid Earth, 122, 4492–4508. https://doi.org/10.1002/2016JB013769
Hansen, S.M., B. Schmandt, A. Levander, E. Kiser, J.E. Vidale, G.A. Abers, K.C. Creager, 2016. Seismic evidence for a cold serpentinized mantle wedge beneath Mount St Helens. Nature Communications, 7, 13242, doi:10.1038/ncomms13242.
Kiser, E., I. Palomeras, A. Levander, C. Zelt, S. Harder, B. Schmandt, S. Hansen, K. Creager, C. Ulberg, 2016. Magma reservoirs from the upper crust to the Moho inferred from high-resolution Vp and Vs models beneath Mount St. Helens, Washington State, USA. Geology, 44, 411–414. https://doi.org/10.1130/G37591.1
Hansen, S.M., B. Schmandt, 2015. Automated detection and location of microseismicity at Mount St. Helens with a large-N geophone array. Geophysical Research Letters, 42, 7390–7397. https://doi.org/10.1038/ncomms13242
| Carl Ulberg and the iMUSH Team, GeoPRISMS Newsletter #39 – Fall 2017 Science Report – Imaging Magma Under Mount St. Helens with Geophysical and Petrologic Methods
| Carl Ulberg and the iMUSH Team, GeoPRISMS Newsletter #34 – Spring 2015 Report from the Field – iMUSH: Imaging Magma Under St. Helens
Press reports are listed on the iMUSH project website
Brandon Schmandt video recordings, part of the GeoPRISMS Lecture Series. University of Oregon, Eugene, OR, May 2018