@article{fdi:010064652,
  title = {{H}ydrothermal and magmatic reservoirs at {L}azufre volcanic area, revealed by a high-resolution seismic noise tomography},
  author = {{S}pica, {Z}. and {L}egrand, {D}. and {I}glesias, {A}. and {W}alter, {T}. {R}. and {H}eimann, {S}. and {D}ahm, {T}. and {F}roger, {J}. {L}. and {R}{\'e}my, {D}ominique and {B}onvalot, {S}ylvain and {W}est, {M}. and {P}ardo, {M}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e determine here for the first time the geometry and location of the hydrothermal and magmatic reservoirs in the {L}azufre volcanic area. {T}his furthers the understanding of the origin of one of the largest worldwide volcanic uplift regions, both in space and amplitude. {T}he exact locations and shapes of the sources generating a double-wide uplift region in the {L}azufre found by past deformation data ({I}n{SAR} and {GPS}) and generating hydrothermal and magmatic fluids found by geochemical gas analysis have not been well-delimited. {I}n this study, we use seismological data to perform a 3-{D} high-resolution {S}-wave velocity model, which allows defining better the locations and shapes of the sources of the deformations and the hydrothermal and magmatic reservoirs. {W}e find three anomalies. {T}wo of them (with {S}-wave velocity of about 1.2-1.8 km/s) are located below the {L}astarria volcano. {T}he shallow one (<1 km below the volcano base) has a funnel-like shape. {T}he deeper one is located between a depth of 3 and 6 km below the volcano base. {B}oth are strongly elliptical in an {EW} direction and separated by a 2-3 km thick zone with {V}s of similar to 1.5-2 km/s. {A}s far as these anomalies are located under the hydrothermal activity of {L}astarria volcano, they are interpreted as a double hydrothermal (the shallow part) and magmatic source (the deeper part). {T}he latter can feed the former. {T}his double hydrothermal and magmatic source is in agreement with previous geochemical, deformation ({GPS} and {I}n{SAR}) and magneto-telluric studies. {I}n particular, it explains the double origin of the gases (hydrothermal and magmatic). {T}he third low-velocity zone (with {S}-wave velocity of about 2.3 km/s) located at 5 km depth and deeper is centered beneath an area of surface uplift as determined by {I}n{SAR} data. {W}e compare the seismic tomography and {I}n{SAR} results to propose that this low-velocity zone is at the top of a large reservoir, hosting hydrothermal fluids and possibly also magma.},
  keywords = {{L}azufre ; {L}astarria ; uplift ; ambient noise tomography ; hydrothermal reservoir ; magma chamber ; {CHILI} ; {ANDES} {CENTRE}},
  booktitle = {},
  journal = {{E}arth and {P}lanetary {S}cience {L}etters},
  volume = {421},
  numero = {},
  pages = {27--38},
  ISSN = {0012-821{X}},
  year = {2015},
  DOI = {10.1016/j.epsl.2015.03.042},
  URL = {https://www.documentation.ird.fr/hor/fdi:010064652},
}