09:00 〜 09:15
[SSS03-01] Scientific applications of the International Monitoring System hydroacoustic component - Remote detection of the recent submarine volcanic eruption at Fukutoku-Okanoba, Bonin Arc
★Invited Papers
キーワード：Fukutoku-Okanoba, Submarine eruption, IMS, CTBTO , Hydroacoustics
As part of the verification regime for the Comprehensive Nuclear-Test-Ban Treaty of 1996, the objective of the International Monitoring System (IMS) is to detect nuclear explosions on land, underground, in the atmosphere, and in the ocean. In addition to radionuclide, seismic, and infrasound monitoring stations, the IMS also includes eleven hydroacoustic receiver sites: Five land-based, high-frequency seismometers and six bottom-moored hydrophone triplets, the latter of which are typically deployed near remote ocean islands and at the depth of the Sound-Fixing-and-Ranging (SOFAR) channel where low-frequency acoustic energy propagates most efficiently.
Here, a recent example for the civil and scientific application of IMS hydrophone data is presented. Acoustic phases associated with the August 2021 eruption at Fukutoku-Okanoba, an active submarine volcano in the southern Bonin Arc, were recorded by IMS station HA11 at Wake Island. The high incidence of arrivals over the initial five-day period of the eruption suggests that during times of activity, the volcano is a prime source of low-frequency underwater sound in the western Pacific Ocean. Combining hydrophone and satellite observations, it is found that the onset times of acoustically detectable activity and the prominent subaerial plume observed at Fukutoku-Okanoba coincide to within a few minutes. These observations further highlight the potential of the IMS hydroacoustic network for remotely detecting and analysing submarine volcanic activity.
Here, a recent example for the civil and scientific application of IMS hydrophone data is presented. Acoustic phases associated with the August 2021 eruption at Fukutoku-Okanoba, an active submarine volcano in the southern Bonin Arc, were recorded by IMS station HA11 at Wake Island. The high incidence of arrivals over the initial five-day period of the eruption suggests that during times of activity, the volcano is a prime source of low-frequency underwater sound in the western Pacific Ocean. Combining hydrophone and satellite observations, it is found that the onset times of acoustically detectable activity and the prominent subaerial plume observed at Fukutoku-Okanoba coincide to within a few minutes. These observations further highlight the potential of the IMS hydroacoustic network for remotely detecting and analysing submarine volcanic activity.