Mount Erebus, a volcano on Ross Island, Antarctica has been in a continuous state of open-vent activity for at least 45 years while hosting a long-lived lava lake at its summit. The volcano's proximity to the United States Antarctic Program McMurdo Station, its longstanding experimental infrastructure, and prior studies present opportunities to develop and apply cutting edge imaging methods to understand a persistently active volcanic system. This project will utilize data from a renovated five-station near-summit seismic network of Mt. Erebus plus three additional stations sited on the flanks of the volcano. This wide aperture network, paired with modern instrumentation and techniques to enhance seismic signal, will provide unprecedented imaging into the deep volcanic plumbing system at crustal scale, which will help researchers understand the volcano's complex structure and processes. Additionally, the network provides year-round seismic data to be used in temporal monitoring efforts for eruptive and other activity. All data from this network will be openly available in near real-time. The real-time data along with an existing catalog of archived data will be analyzed using recently developed methods to generalize, recognize, quantify, and catalog eruptive events. The project objectives are to study the response of the magmatic system to such events and use continuously recorded background noise and eruption signals to infer concurrent structural changes. These seismic investigations into the long-term changes of the volcano, tracking broad phenomena such as the subsidence of Ross Island, will also be complemented by GPS recordings of deformation. These activities will help test hypotheses related to the structure of the deeper magmatic system of Erebus and the properties of the material surrounding this system. The project funds two early-career scientists and three graduate students, contributing to the development of the next generation of volcanologists and seismologists.
This award results in the establishment of a first-tier monitoring system and catalogues eruptive events using real-time seismic and infrasound data. Synoptic analysis of broadband signals recorded by the updated seismic network will allow monitoring and interpretation of pre and post eruptive response and conduit evolution via measurements of systematic timing changes of short-period (explosion) versus very long-period (conduit) seismogram signatures. These observations will be supplemented by the interpretation of broadband seismic tilt in association with existing UNAVCO-supported GPS data over time scales from hours to years. Longer-period coda correlation back projection will be used to refine upper edifice structural information and teleseismic signals will be analyzed to examine the bulk and discontinuity structure of the underlying crust. The work includes a reanalysis of archived TOMO Erebus broadband, as well as extensive short-period data collected in 2007-2008. This effort will allow new imaging and interpretation of deeper (e.g., crustal to Moho-or-deeper scale) structure than has been previously imaged at Erebus in consort with other constraints, such as emerging magnetotelluric imaging results for Erebus and Ross Island. The researchers will use the year-round continuous stations to time-lapse interrogate prominent and repeatable structural/internal scattering features revealed by both ambient noise and eruption or other signal coda correlations. Joint inversions of H/V ratios for both coda and ambient noise coupled with dispersion curves assembled from the fusion of ambient noise (low frequency) and coda (high frequency) will complement direct imaging of strong near-surface scatterers and will be applied to archived ETB/ETS data sets. Cutting edge reflection matrix techniques will continue to be developed in collaboration with independently funded groups in France to further isolate and define high scattering bodies within the top 10 kilometers of the crust and edifice. This award is cofunded by the Prediction of and Resilience against Extreme Events (PREEVENTS) program.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
