@article{PAR00008906,
  title = {{E}ruptive history of {C}himborazo volcano ({E}cuador) : a large, ice-capped and hazardous compound volcano in the {N}orthern {A}ndes},
  author = {{S}amaniego, {P}ablo and {B}arba, {D}. and {R}obin, {C}laude and {F}ornari, {M}ichel and {B}ernard, {B}enjamin},
  editor = {},
  language = {{ENG}},
  abstract = {{N}ew fieldwork, radiometric and whole-rock chemical data permit the reconstruction of the main eruptive stages of the {C}himborazo compound volcano, the highest summit of the {N}orthern {A}ndes. {C}himborazo is composed of three successive edifices. {T}he {B}asal {E}difice ({CH}-{I}) was active from similar to 120 to 60 ka and resulted in a large, mostly effusive edifice which was built up during two stages of cone-building, terminating with the formation of a dome complex. {T}his edifice was affected by a huge sector collapse around 65-60 ka which produced a major debris avalanche that spread out into the {R}iobamba basin, covering about 280 km(2) with an average thickness of 40 m and a total volume of similar to 10-12 km(3). {A}fter the emplacement of the {R}iobamba debris avalanche, eruptive activity resumed at the eastern outlet of the avalanche scar and was responsible for the construction of a less voluminous, {I}ntermediary {E}difice ({CH}-{II}), whose current remnants are the {P}olitecnica and {M}artinez peaks. {T}his edifice developed from 60 to 35 ka. {L}astly, eruptive activity shifted to the west, leading to the construction of the morphologically well-preserved {Y}oung {C}one ({CH}-{I}ll) which currently forms the highest summit ({W}hymper). {T}he average eruptive rate of {C}himborazo volcano is 0.5-0.7 km(3)/ka. {H}owever, looking at the three successive edifices individually, we estimate that there has been a progressive decrease in magma output rate from the {B}asal {E}difice (0.7-1.0 km(3)/ka), through the {I}ntermediary {E}difice (0.4-0.7 km(3)/ka) to the {Y}oung {C}one (similar to 0.1 km(3)/ka). {H}owever, during the main cone-building stages, the peak eruption rates are markedly higher, indicating significant variations in the magma output rate during the lifespan of this arc volcano. {D}uring the {H}olocene, the {C}himborazo eruptive activity consisted of small-volume explosive events that occurred at quite regular intervals, between about 8000 and 1000 yr ago. {S}ince the last eruption occurred between the early part of the 5th century and the end of the 7th century, and the average time interval between the events is about 1000 yr. {C}himborazo must be considered as a potentially active volcano. {T}he presence of a thick ice cap covering the summit, its steep flanks and its position above the populated lowland area of {R}iobamba and {A}mbato, are factors that result in a high potential risk.({C}) 2012 {E}lsevier {B}.{V}. {A}ll rights reserved.},
  keywords = {{C}himborazo ; {A}ndean volcanism ; {L}ate {P}leistocene ; {E}ruptive rates ; {V}olcanic hazards ; {A}r-40-{A}r-39 geochronology},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {221},
  numero = {},
  pages = {33--51},
  ISSN = {0377-0273},
  year = {2012},
  DOI = {10.1016/j.jvolgeores.2012.01.014},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00008906},
}