@article{fdi:010061782,
  title = {{T}he 2006-2009 activity of the {U}binas volcano ({P}eru) : petrology of the 2006 eruptive products and insights into genesis of andesite magmas, magma recharge and plumbing system},
  author = {{R}ivera, {M}. and {T}houret, {J}. {C}. and {S}amaniego, {P}ablo and {L}e {P}ennec, {J}ean-{L}uc},
  editor = {},
  language = {{ENG}},
  abstract = {{F}ollowing a fumarolic episode that started six months earlier, the most recent eruptive activity of the {U}binas volcano (south {P}eru) began on 27 {M}arch 2006, intensified between {A}pril and {O}ctober 2006 and slowly declined until {D}ecember 2009. {T}he chronology of the explosive episode and the extent and composition of the erupted material are documented with an emphasis on ballistic ejecta. {A} petrological study of the juvenile products allows us to infer the magmatic processes related to the 2006-2009 eruptions of the andesitic {U}binas volcano. {T}he juvenile magma erupted during the 2006 activity shows a homogeneous bulk-rock andesitic composition (56.7-57.6 wt.% {S}i{O}2), which belongs to a medium- to high-{K} calc-alkaline series. {T}he mineral assemblage of the ballistic blocks and tephra consists of plagioclase > two-pyroxenes > {F}e-{T}i oxide and rare olivine and amphibole set in a groundmass of the same minerals with a dacitic composition (66-67 wt.% {S}i{O}2). {T}hermo-barometric data, based on two-pyroxene and amphibole stability, records a magma temperature of 998 +/- 14 degrees {C} and a pressure of 476 +/- 36 {MP}a. {W}idespread mineralogical and textural features point to a disequilibrium process in the erupted andesite magma. {T}hese features include inversely zoned "sieve textures" in plagioclase, inversely zoned clinopyroxene, and olivine crystals with reaction and thin overgrowth rims. {T}hey indicate that the pre-eruptive magmatic processes were dominated by recharge of a hotter mafic magma into a shallow reservoir, where magma mingling occurred and triggered the eruption. {P}rior to 2006, a probable recharge of a mafic magma produced strong convection and partial homogenization in the reservoir, as well as a pressure increase and higher magma ascent rate after four years of fumarolic activity. {M}afic magmas do not prevail in the {U}binas pre-historical lavas and tephras. {H}owever, mafic andesites have been erupted during historical times (e.g. {AD} 1667 and 2006-2009 vulcanian eruptions). {H}ence, the most recent episode indicates that a resupply of mafic magmas has probably occurred at depth under {U}binas.},
  keywords = {{E}xplosive activity ; {M}agma recharge ; {M}agma mixing ; {T}hermobarometry ; {U}binas ; {P}eru ; {PEROU} ; {ANDES}},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {270},
  numero = {},
  pages = {122--141},
  ISSN = {0377-0273},
  year = {2014},
  DOI = {10.1016/j.jvolgeores.2013.11.010},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061782},
}