Infrasound monitoring for Marianas volcanoes 26 February 2010Posted by admin in Pacific, United States, volcano monitoring.
Tags: infrasound, Northern Marianas Islands, Pacific, Southern Methodist University, United States, USGS, volcano monitoring
Left: Pagan erupting, 18 May 1981. Right: Anatahan erupting, 16 June 2003. (Both images courtesy USGS.)
A new programme in the Northern Marianas Islands will use infrasound technology alongside conventional seismometers and other equipment to monitor the archipelago’s active volcanoes. The partners behind the project to enhance volcano monitoring in the Marianas are the Northern Marianas Commonwealth Government, the U. S. Geological Survey and Southern Methodist University (SMU). SMU scientists have been responsible for the application of infrasound to the detection of nuclear explosions in order to monitor test ban compliance.
The project chief, Professor James Quick, explains that infrasound used alongside conventional monitoring techniques will add a new dimension to the interpretation of volcanic signals: ‘My hope is that we’ll see some distinctive signals in the infrasound that will allow us to discriminate the different kinds of eruptive styles — from effusive events that produce lava flows, or small explosive events we call vulcanian eruptions, to the large “Plinian” events of particular concern to aviation. They are certain to have some characteristic sonic signature’.
The planned development of the Marianas as a forward deployment base for the United States military has given particular urgency to the improvement of volcano monitoring in the archipelago.
Volcanic eruptions produce much more sound than human ears can detect – in particular, they are prolific and efficient radiators of low-frequency sound, in the infrasonic bandwith below the threshold of human hearing. These low-frequency sounds are detectable at great distances and are little affected by passage through the atmosphere. Volcano monitoring using infrasound offers several benefits:
- It is unaffected by inclement weather, darkness and poor visibility.
- It offers the potential for a detailed understanding of internal volcanic dynamics in both eruptive and non-eruptive states.
- It avoids the complication of variations in local conditions and monitoring arrangements, making comparisons between different volcanoes easier.
- It can be used to clarify and interpret obscure and enigmatic seismicity.
More information about volcanic infrasound monitoring can be found at the INFRAVOLC site run by New Mexico Tech.
USGS-SMU volcano monitoring will target hazard threat to Marianas, U.S. military and commercial jets – SMU News Release, 24 February 2010*
Global Volcanism Program: Anatahan – information about Anatahan (0804-20=)
Global Volcanism Program: Pagan – information about Pagan (0804-17=)
Northern Mariana Islands volcanic activity – from the Marianas government
North Pacific Volcanic Islands – information from the USGS
* Lots of detail in the news release, but it contains two Wikipedia links, ugh. A reputable university should know better.