Probing the Atmosphere and Atmospheric Sources with the USArray

Probing the Atmosphere and Atmospheric Sources with the USArray A record section to the west of the event. We see two acoustic branches (at celerities from 225 to 312 m/s) to a range of over 300 km in this direction.
The USArray is designed to image the subsurface structure of the United States with exceptional resolution at a continental scale and for studies of regional and teleseismic earthquakes. Although the sensors of this network directly measure ground motion, they indirectly measure other phenomena that affect ground motion. It has been known for a long time that infrasound can be detected by seismometers through acoustic-to-seismic conversion at the ground/atmosphere interface. The USArray data archive contains recordings of several hundred large atmospheric events. One example is a bolide that burst above Oregon State on February 19, 2008 and was recorded by several hundred seismic stations and four infrasound arrays. The bolide source parameters were precisely determined by the seismic data, and the time-offset records show several phase branches corresponding to multiple arrivals. Such branches have never before been observed in such spectacular detail because infrasound arrays separated by thousands of kilometers are typically used for infrasound studies. The branches from such a large number of events occurring through the year are proving to be very useful for study of infrasound propagation and atmospheric structure.
</p><p>Acknowledgements: We would like to acknowledge Earthscope and IRIS for data from the USArray without which this study would not have been possible. We would like to thank Matt Fouch at the University of Arizona and David James at the Carnegie Institution of Washington for giving us access to data from their High Lava Plains Seismic Experiment. We would also like to thank Gene Humphries at the University of Oregon for giving us access to data from the Wallowa Flexible Array Experiment. This article was made possible through support provided by US Army Space and Missile Defense Command. The opinions expressed herein are those of the authors and do not necessarily reflect the views of the US Army Space and Missile Defense Command.</p>


No comments yet.



Welcome to the IRIS Image Gallery – a diverse collection of photographs and visuals that encompass the range and breadth of seismology and the seismological community.

Please browse through our albums. These low and medium-resolution images can be freely used for personal and educational/academic purposes, but we request you recognize the image contributor by including in your product or presentation the credit displayed with each image.

More information is available in the Image Use Agreement.

If you have any comments, questions, or suggestions related to the IRIS Image Gallery, you can send them to

Photo info

Popular tags