Ultra-long-range hydroacoustic observations of submarine volcanic activity at Monowai, Kermadec Arc

• Published in: Geophysical Research Letters
• Main Authors: Metz, D., Watts, Anthony B., Grevemeyer, I., Rodgers, M., Paulatto, M.
• Other Authors: Department of Earth Sciences Oxford, University of Oxford, Helmholtz Centre for Ocean Research Kiel (GEOMAR), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud )
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Pacific; South Atlantic Ocean
• Online Access: https://hal.science/hal-01347208; https://hal.science/hal-01347208/document; https://hal.science/hal-01347208/file/2015GL067259.pdf; https://doi.org/10.1002/2015GL067259

International audience 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