Virtual array beamforming of GPS TEC observations of coseismic ionospheric disturbances near the Geomagnetic South Pole triggered by teleseismic megathrusts

Authors

Demián Gõmez, University of Memphis
Robert Smalley, University of Memphis
Charles A. Langston, University of MemphisFollow
Terry J. Wilson, The Ohio State University
Michael Bevis, The Ohio State UniversityFollow
Ian W.D. Dalziel, Jackson School of GeosciencesFollow
Eric C. Kendrick, The Ohio State UniversityFollow
Stephanie A. Konfal, The Ohio State University

Abstract

We identified coseismic ionospheric disturbances (CID) in Antarctica generated by the 2010 Maule and the 2011 Tohoku-Oki earthquakes analyzing total electron content (TEC) data with a modified beamforming technique. Beamforming in Antarctica, however, is not straightforward due to the effects of array deformation and atmospheric neutral wave-ionospheric plasma coupling. We take these effects into account and present a method to invert for the seismically generated acoustic wave using TEC observations. The back azimuths, speeds, and waveforms obtained by the beamform are in excellent agreement with the hypothesis that the TEC signals are generated by the passage of Rayleigh waves from the Maule and Tohoku-Oki earthquakes. The Tohoku-Oki earthquake is ~12,500 km from Antarctica, making this the farthest observation of CIDs to date using GPS.

Publication Title

Journal of Geophysical Research A: Space Physics

Recommended Citation

Gõmez, D., Smalley, R., Langston, C., Wilson, T., Bevis, M., Dalziel, I., Kendrick, E., & Konfal, S. (2015). Virtual array beamforming of GPS TEC observations of coseismic ionospheric disturbances near the Geomagnetic South Pole triggered by teleseismic megathrusts. Journal of Geophysical Research A: Space Physics, 120 (10), 9087-9101. https://doi.org/10.1002/2015JA021725