@article{fdi:010061786,
  title = {{A}nalysis of dynamics of vulcanian activity of {U}binas volcano, using multicomponent seismic antennas},
  author = {{I}nza, {L}. {A}. and {M}{\'e}taxian, {J}ean-{P}hilippe and {M}ars, {J}. {I}. and {B}ean, {C}. {J}. and {O}'{B}rien, {G}. {S}. and {M}acedo, {O}. and {Z}andomeneghi, {D}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A} series of 16 vulcanian explosions occurred at {U}binas volcano between {M}ay 24 and {J}une 14, 2009. {T}he intervals between explosions were from 2.1 h to more than 6 days (mean interval, 33 h). {C}onsidering only the first nine explosions, the average time interval was 7.8 h. {M}ost of the explosions occurred after a short time interval (<8 h) and had low energy, which suggests that the refilling time was not sufficient for large accumulation of gas. {A} tremor episode followed 75% of the explosions, which coincided with pulses of ash emission. {T}he durations of the tremors following the explosions were longer for the two highest energy explosions. {T}o better understand the physical processes associated with these eruptive events, we localized the sources of explosions using two seismic antennas that were composed of three-component 10 and 12 sensors. {W}e used the high-resolution {MUSIC}-3{C} algorithm to estimate the slowness vector for the first waves that composed the explosion signals recorded by the two antennas assuming propagation in a homogeneous medium. {T}he initial part of the explosions was dominated by two frequencies, at 1.1 {H}z and 1.5 {H}z, for which we identified two separated sources located at 4810 m and 3890 m +/- 390 altitude, respectively. {T}he position of these two sources was the same for the full 16 explosions. {T}his implies the reproduction of similar mechanisms in the conduit. {B}ased on the eruptive mechanisms proposed for other volcanoes of the same type, we interpret the position of these two sources as the limits of the conduit portion that was involved in the fragmentation process. {S}eismic data and ground deformation recorded simultaneously less than 2 km from the crater showed a decompression movement 2 s prior to each explosion. {T}his movement can be interpreted as gas leakage at the level of the cap before its destruction. {T}he pressure drop generated in the conduit could be the cause of the fragmentation process that propagated deeper. {B}ased on these observations, we interpret the position of the highest source as the part of the conduit under the cap, and the deeper source as the limit of the fragmentation zone.},
  keywords = {{V}olcano seismic monitoring ; {S}eismic array ; {V}ulcanian activity ; {U}binas ; {PEROU} ; {ANDES}},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {270},
  numero = {},
  pages = {35--52},
  ISSN = {0377-0273},
  year = {2014},
  DOI = {10.1016/j.jvolgeores.2013.11.008},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061786},
}