Citation

Arrowsmith SJ, Burlacu R, Pankow K, Stump B, Stead R, Whitaker R, Hayward C. J. Acoust. Soc. Am. 2012; 132(3): 2047.

Affiliation

Geophysics Group, Los Alamos National Laboratory, 1711 Second Street, Santa Fe, NM 87505sarrowsmith@gmail.com.

Copyright

(Copyright © 2012, American Institute of Physics)

DOI

10.1121/1.4755526

PMID

22979608

Abstract

Earthquakes can generate complex seismo-acoustic wavefields, consisting of seismic waves, epicenter-coupled infrasound, and secondary infrasound. We report on the development of a numerical seismo-acoustic model for the generation of infrasound from earthquakes. We model the generation of seismic waves using a 3D finite difference algorithm that accounts for the earthquake moment tensor, source time function, depth, and local geology. The resultant acceleration-time histories (on a 2D grid at the surface) provide the initial conditions for modeling the near-field infrasonic pressure wave using the Rayleigh integral. Finally, we propagate the near-field source pressure through the Ground-to-Space atmospheric model using a time-domain parabolic equation technique. The modeling is applied to an earthquake of MW 4.6, that occurred on January 3, 2011 in Circleville, Utah; the ensuing predictions are in good agreement with observations made at the Utah network of infrasonic arrays, which are unique and indicate that the signals recorded at 6 arrays are from the epicentral region. These results suggest that measured infrasound from the Circleville earthquake is consistent with the generation of infrasound from body waves in the epicentral region.

Language: en