Japan Geoscience Union Meeting 2015

Presentation information


Symbol M (Multidisciplinary and Interdisciplinary) » M-TT Technology & Techniques

[M-TT41] Brand-new scope of coupling geophysics being established by infrasound and associated waves

Tue. May 26, 2015 6:15 PM - 7:30 PM Convention Hall (2F)

Convener:*Masa-yuki Yamamoto(Department of systems engineering, Kochi University of Technology), Nobuo Arai(Disaster Mitigation Research Center, Nagoya University)

6:15 PM - 7:30 PM

[MTT41-P04] Recent progress of infrasound studies and sensor developing activities

*Masa-yuki YAMAMOTO1, Akihiro YOKOTA2 (1.Kochi University of Technology, 2.SESONA ALES)

Keywords:Infrasound, Multsites observation, Sensor development, Hazard prevention, Polar region observation, Collaboration of science and engineering

Infrasound is one of the most important open fields to study the missing link from troposphere to upper atmosphere. In this decade, observation of the infrasound has been gradually improved with the progress of constructing the sensor network in all over the world for watching the nuclear explosions. On the other hand, many kinds of remote-sensing observing methods have been developed by many scientists for ionspheric plasma observation like the GPS-TEC mapping method to clarify the wide field disturbances like TID (Traveling Ionospheric Disturbance), indicating the importance of vertically propagating large wavelength waves to be projected and seen on the mapping results. Seismic, volcanic, atmospheric and oceanic observation regions are also deeply concerning with the infrasound studies.
Hence, not only the electromagnetic coupling processes but also neutral atmospheric pressure waves like the audible sound and infrasound should be studied. However, the observation of infrasound is currently less sufficient rather than the seismic and GPS sensor networks. As for the event studies, it has been reported that huge earthquakes like Smatra (2004) or Tohoku-oki (2011) as well as their induced tsunami waves became clear wave sources of these kinds of pressure waves, suggesting the infrasound whose propagating velocity is faster than that of tsunami waves on the sea is important for the disaster prevention. Even the relatively small scale geophysical phenomena like volcanic eruptions, meteorite entries, land or snow slides, or thunders also creates clear N type infrasound signal at a time of arrival of the shock waves generated at the source region, possibly depending on its size and moving distance.
In order to measure such pressure waves in a few to several 100 km scale, arrayed sensors network is required, thus the cost of each pressure sensor is important to built. We recently developed a new infrasound sensor that include some weather monitoring sensors and seismometers, enables us to integrate several parameters information to create an independent emergency alert system by one sensor complex for any geophysical events just after the arrival of the sonic waves. In this paper, we will show the most recent progress of the infrasound studies as well as the development of infrasound sensors. Collaboration of science and engineering researches, manufacturing companies with their engineers and infrastructure management officers in regional governments are very important to open the new era of the infrasound applications useful into the society.