Attenuation and scattering tomography of the deep plumbing system of Mount St. Helens

L. De Siena, C. Thomas, G. P. Waite, S. C. Moran, S. Klemme

Research output: Contribution to journalArticlepeer-review

54 Citations (Scopus)
13 Downloads (Pure)


We present a combined 3D P-wave attenuation, 2D S-coda attenuation, and 3D S-coda scattering tomography model of fluid pathways, feeding systems, and sediments below Mount St. Helens (MSH) volcano between depths of 0 and 18 km. High-scattering and high-attenuation shallow anomalies are indicative of magma and fluid-rich zones within and below the volcanic edifice down to 6 km depth, where a high-scattering body outlines the top of deeper aseismic velocity anomalies. Both the volcanic edifice and these structures induce a combination of strong scattering and attenuation on any seismic wave-field, particularly those recorded on the northern and eastern flanks of the volcanic cone. North of the cone between depths of 0 and 10 km a low-velocity, high-scattering, and high-attenuation north-south trending trough is attributed to thick piles of Tertiary marine sediments within the St. Helens Seismic Zone. A laterally-extended 3D scattering contrast at depths of 10 to 14 km is related to the boundary between upper and lower crust, and caused in our interpretation by the large scale interaction of the Siletz terrane with the Cascade arc crust. This
contrast presents a low-scattering, 4-6 km ”hole” under the north-eastern flank of the volcano. We infer that this section represents the main path of magma ascent from depths greater than 6 km at MSH, with a small north-east shift in the lower plumbing system of the volcano. We conclude that combinations of different non-standard tomographic methods, leading toward full-waveform
tomography, represent the future of seismic volcano imaging.
Original languageEnglish
Pages (from-to)8223-8238
Number of pages16
JournalJournal of Geophysical Research: Solid Earth
Issue number11
Early online date7 Nov 2014
Publication statusPublished - Nov 2014

Bibliographical note

We thank Edoardo Del Pezzo, Ludovic Margerin, Christoph Sens‐Schönefelder, Michael Becken, David Hill, Matt Haney, Willie Scott, Alicia Hotovec‐Ellis, Jonathan Lees, and two anonymous reviewers for their suggestions and critical reviews. Steve Hicks, Carina Häger, and Laura Schmidt helped in the data processing. The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for access to waveform and metadata required in this study and provided by the Cascades Volcano Observatory ‐ USGS. The MuRAT code with two sample applications is freely available at http://earth.uni‐ under free license. The methods for the 2‐D and 3‐D scattering tomographies are based on the ones described in Tramelli et al. [2006] and Calvet et al. [2013]. Supporting information accompanies this paper. Correspondence and requests for materials should be addressed to Luca De Siena.


  • attenuation tomography
  • scattering tomography
  • volcano tomography


Dive into the research topics of 'Attenuation and scattering tomography of the deep plumbing system of Mount St. Helens'. Together they form a unique fingerprint.

Cite this