IS40 and Infrasound waves from volcanic eruptions

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IS40 and Infrasound waves from volcanic eruptions

• Itikarai, I., Campus, P., Martysevich, P.,
  Hoffmann, T.

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Presentation Outline

• Tectonics and volcanism in PNG
• Volcanic eruptions in PNG
• Infrasound station IS40 site survey
• Noise level measurements
• Noise generating phenomena
• Site survey recommendations
• Current status for IS40 development

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Tectonics and volcanism in Papua New Guinea
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Location of Papua New Guinea
Papua New Guinea
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General tectonics of Papua New Guinea
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Seismicity of Papua New Guinea
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Active volcanoes of Papua New Guinea
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Volcanic eruptions in Papua New Guinea
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Volcanic eruptions in Papua New Guinea
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Eruption type and degree of explosivity and
number of PNG volcanoes bearing each type.
Degree of explosivity Very high Very low
Eruption type
No. showing this type
Percentage showing this type
Plinian Peleean Vulcanian Strombo
vulc. Strombolian Baganian Underwater
1 6 7 4 5 1 4
7 43 50 29 36 7 29
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PNG volcanic eruptions and VEIs
Volcano Eruption Year
VEI Lamington 1951 4 Karkar
1979 3-4 Rabaul 1994 4 Manam
1996 2-3 Ulawun 2001 2-3 Pago
2002 0-1 Note There have been major volcanic
eruptions with VEIs 5 and 6. Examples
of these type of eruptions are to have
occurred in Rabaul and Witori volcanic systems.
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1994 Rabaul eruptions (Tavurvur and Vulcan)
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Vulcan eruption - 1994
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IS40 Site Survey
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Locality for site survey
Rabaul
(A)
(C)
(B)
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Proposed configuration for IS40
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Vegetation cover of surveyed area
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Infrasound station IS40 Site survey
(a) Noise level measurements
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Simultaneous micropressure readings

• connected to noise-
• reducing porous hose

• open

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Infrasound station IS40 Site survey
(b) Noise generating phenomena
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Microbarom power density spectra
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Shear-generated gravity waves
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High frequency infrasonic waves from volcanic
activity
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Volcanic events
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Seismic and infrasound waves
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Volcanic activity power density spectra
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Seismogram for an volcanic explosion
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Seismogram for an volcanic explosion
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Amplitude spectra for a volcanic explosion event
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Amplitude spectra for a volcanic explosion event
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Vulcanian explosion from Tavurvur
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Other possible local sources of infrasound waves

• Thunderstorm/lightning
• dynamite

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Infrasound station IS40 Site survey
recommendations
(a) Proposed IS40 location is site A from the
site survey (b) 8-element infrasound array is
recommended with wind-noise reduding pipe
arrays (c) Power source will be 12 volts
DC (e) Radio telemetry to link each array
element
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Current status of IS40

• Proposed location for IS40 from site survey
  endorsed
• Identification of contractors for civil works
• construction of CPF
• construction of infrastructure for array elements