Print Email Facebook Twitter Evanescent wave coupling in a geophysical system: Airborne acoustic signals from the Mw 8.1 Macquarie Ridge earthquake Title Evanescent wave coupling in a geophysical system: Airborne acoustic signals from the Mw 8.1 Macquarie Ridge earthquake Author Evers, L.G. Brown, D. Heaney, K.D. Assink, J.D. Smets, P.S.M. Snellen, M. Faculty Civil Engineering and Geosciences Department Geoscience & Engineering Date 2014-03-10 Abstract Atmospheric low-frequency sound, i.e., infrasound, from underwater events has not been considered thus far, due to the high impedance contrast of the water-air interface making it almost fully reflective. Here we report for the first time on atmospheric infrasound from a large underwater earthquake (Mw 8.1) near the Macquarie Ridge, which was recorded at 1325 km from the epicenter. Seismic waves coupled to hydroacoustic waves at the ocean floor, after which the energy entered the Sound Fixing and Ranging channel and was detected on a hydrophone array. The energy was diffracted by a seamount and an oceanic ridge, which acted as a secondary source, into the water column followed by coupling into the atmosphere. The latter results from evanescent wave coupling and the attendant anomalous transparency of the sea surface for very low frequency acoustic waves. Subject earthquakeseismologyinfrasoundhydroacoustics To reference this document use: http://resolver.tudelft.nl/uuid:50b48792-8ebf-4563-80d8-0b70b151318e DOI https://doi.org/10.1002/2013GL058801 Publisher American Geophysical Union Embargo date 2014-09-10 ISSN 0094-8276 Source Geophysical Research Letters, 41 (5), 2014 Part of collection Institutional Repository Document type journal article Rights © 2014 American Geophysical Union Files PDF Evers_2014.pdf 4.27 MB Close viewer /islandora/object/uuid:50b48792-8ebf-4563-80d8-0b70b151318e/datastream/OBJ/view