Ultra‐long‐range hydroacoustic observations of submarine volcanic activity at Monowai, Kermadec Arc. Issue 4 (22nd February 2016)

• Record Type: Journal Article
• Authors: Metz, D.; Watts, A. B.; Grevemeyer, I.; Rodgers, M.; Paulatto, M.
• Is Part Of: Geophysical research letters. Volume 43:Issue 4(2016)
• Page Start: 1529
• Page End: 1536
• Publication Date: 2016-02-22
• Subjects: T phase -- Hydroacoustics -- Monowai -- CTBTO; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL067259
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Monowai is an active submarine volcanic center in the Kermadec Arc, Southwest Pacific Ocean. During May 2011, it erupted over a period of 5 days, with explosive activity directly linked to the generation of seismoacoustic T phases. We show, using cross‐correlation and time‐difference‐of‐arrival techniques, that the eruption is detected as far as Ascension Island, equatorial South Atlantic Ocean, where a bottom moored hydrophone array is operated as part of the International Monitoring System of the Comprehensive Nuclear‐Test‐Ban Treaty Organization. Hydroacoustic phases from the volcanic center must therefore have propagated through the Sound Fixing and Ranging channel in the South Pacific and South Atlantic Oceans, a source‐receiver distance of ~15, 800 km. We believe this to be the furthest documented range of a naturally occurring underwater signal above 1 Hz. Our findings, which are consistent with observations at regional broadband stations and long‐range, acoustic parabolic equation modeling, have implications for submarine volcano monitoring. Key Points: T phase arrivals at Ascension Island can be linked to a submarine eruption at Monowai, Kermadec Arc T phases must have traveled along the SOFAR channel and over a geodesic range of ~15, 800 km Our results are confirmed by correlation with broadband seismic data and transmission loss modeling