itw2007: p. campus tokyo, 13-16 november 2007 the ims infrasound network: detection of a large...

ITW2007: P. Campus Tokyo, 13-16 November 2007

The IMS Infrasound Network: detection of a large variety of events, including volcanic

eruptionsDr. Paola Campus,

Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) IMS, Installation and Certification Group, Acoustic Monitoring Project

e-mail: [email protected]



Examples of infrasound signals


The International Monitoring

System (IMS) Infrasound Network


Earthquakes

Irian Jaya, 2002/10/10, Mw=7.5IS07, Warramunga, NT, Australia:

~2000km


Irian Jaya, 2002/10/10, Mw=7.5IS07


Irian Jaya, 2002/10/10, Mw=7.5IS07: seismic waves


Irian Jaya, 2002/10/10, Mw=7.5IS07: infrasound waves


Infrasound might help complement the information about earthquakes especially

when, for local events, local seismic networks are very sparse or non existing

Earthquakes


Bolides

Chicago fireball, 2003/03/27


A few minutes after midnight (local time) on March 27, 2003, a huge bolide entered

the atmosphere, moving across Ohio, Illinois, Indiana and Wisconsin and

producing a luminous blue flash.

Fragments of the bolide hit an inhabited area of about 10 km, located south of

Chicago.

Chicago fireball


Chicago fireball, IS10, Lac du Bonnet, Canada: ~1170km


Two different bolides following two different trajectories?



Movements of glaciers and calving of icebergs

IS18, Qaanaaq, Northern Greenland, Danemark


IS18, Qaanaaq, Northern Greenland


IS18, infrasound signals: freq. 0.4-6 Hz


IS18: long duration infrasound signal freq. 0.4-6 Hz


Slow movement of glacier or tide associated to it?

IS18: long duration infrasound signal freq. 0.4-6 Hz


IS18: short duration infrasound signal 1: freq. 0.4-6 Hz


Infrasound might help monitor the effects of global warming through the systematic observation of movements of glaciers and

calving of icebergs

Movements of glaciers and calving of icebergs


Volcanoes


Volcanic hazard: a serious threat to

-Nearby settlements-Civil Aviation

The IMS Infrasound Network can contribute to volcano monitoring


The increased number of IMS Infrasound Stations allows us to monitor several active volcanic

areas around the world


Aleutian Islands


AUGUSTINE Alaska, Aleutian Islands,

Kamishak Bay, Southern Cook Inlet 59.363N, 153.43W; summit elev. 1,252 m

Augustine is the most active volcano of the eastern Aleutian arc.

On January 13, 2006 the volcano entered a period of repetitive and explosive eruptions. Each event produced

ash plumes, mudflows, and pyroclastic flows

Volcanoes


AUGUSTINE, 59.363N, 153.43W, 1252m


IS53: Dist. ~ 675 km; Prop.Time ~00:37

Frequency band: 0.4-8 Hz


Kamchatka Peninsula


KARYMSKY Kamtchatka Peninsula, Russian Federation 54.05°N, 159.43°E; summit elev. 1,536 m

Karymsky is the most active volcano of the eastern volcanic zone of Kamtchatka.

Growth of the lava dome since the end of 2005. Several ash explosions on the beginning of 2006.

First example: ash plumes registered on 2006/01/12. No origin time was available

Volcanoes


KARYMSKY, 54.0N, 159.5E, 4875m


IS44, Petropavlovsk-Kamchatski, Russian Federation


IS44: Dist.~154km; Prop.Time ~00:08



KARYMSKY

Two events close in time, with no significant variation in the meteorological conditions

(wind speed, wind direction, temperature):

the difference in the waveforms can be associated to differences in the source

Volcanoes


KARYMSKY

From 07 May to 14 May the seismicity was above background levels, with 330-450 shallow

earthquakes per day. Based on seismic data, possible ash and gas explosions.

No origin time was available

Volcanoes


IS44: Dist.~154km; Prop.Time ~00:08



The presence of an infrasound station in a volcanic area can be extremely useful to

monitor the beginning of an eruption and to define its origin time. In addition, an

infrasound station can be used both as a unique volcano monitoring tool in case other

monitoring systems are not available (or cannot be used), and as a complementary tool to other, already existing, monitoring systems.


The IMS Infrasound Network is not only a powerful tool to monitor nuclear explosions, but it can also provide a significant contribution to monitor natural events:•Complement or provide information about earthquakes •Complement or provide information about bolides, meteorites, auroras•Monitor effects of global warming•Complement or provide information about volcanic eruptions (origin time, source characteristics)

Conclusions

itw2007: p. campus tokyo, 13-16 november 2007 the ims infrasound network: detection of a large...

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