TY - JOUR
T1 - Monotonic infrasound and Helmholtz resonance at Volcan Villarrica (Chile)
AU - Goto, A.
AU - Johnson, J. B.
PY - 2011/3/1
Y1 - 2011/3/1
N2 - Monotonic infrasound with stable peaked frequency of 0.77 Hz was recorded at Volcan Villarrica in January 2010. Similar monotonic infrasound had been previously reported at Villarrica (e.g., Ripepe et al. [2010]). Using joint infrasound and visual observations from a suspended camera we demonstrate that the likely source of infrasound is Helmholtz resonance produced from a cavity with volume 105 m3 that separates the active convecting lava lake from an overhanging spatter roof. Spatter roof dimension (65 m diameter) and vent diameter (10 m) in the roof are constrained from video observations. Assuming a cylindrical cavity we infer a cavity height of 31 m that is corroborated by video records of spatter drips. The drips take as long as 2.2 s to fall from the roof into the lake, corresponding to a height of more than 24 m, which is in good agreement with the observed resonance frequency.
AB - Monotonic infrasound with stable peaked frequency of 0.77 Hz was recorded at Volcan Villarrica in January 2010. Similar monotonic infrasound had been previously reported at Villarrica (e.g., Ripepe et al. [2010]). Using joint infrasound and visual observations from a suspended camera we demonstrate that the likely source of infrasound is Helmholtz resonance produced from a cavity with volume 105 m3 that separates the active convecting lava lake from an overhanging spatter roof. Spatter roof dimension (65 m diameter) and vent diameter (10 m) in the roof are constrained from video observations. Assuming a cylindrical cavity we infer a cavity height of 31 m that is corroborated by video records of spatter drips. The drips take as long as 2.2 s to fall from the roof into the lake, corresponding to a height of more than 24 m, which is in good agreement with the observed resonance frequency.
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U2 - 10.1029/2011GL046858
DO - 10.1029/2011GL046858
M3 - Article
AN - SCOPUS:79952924598
SN - 0094-8276
VL - 38
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 6
M1 - L06301
ER -