@article{fdi:010088910,
  title = {{W}hat controls the formation of vulcanian bombs ? {A} case study from the 1 {F}ebruary 2014 eruption of {T}ungurahua ({E}cuador)},
  author = {{F}alasconi, {A}. and {C}ioni, {R}. and {B}ernard, {B}. and {S}amaniego, {P}ablo and {P}istolesi, {M}. and {S}chiavi, {F}ederica},
  editor = {},
  language = {{ENG}},
  abstract = {{V}ulcanian eruptions are very common at many volcanoes around the world that erupt intermediate to silicic magmas. {T}his type of eruption generates a wide variability of bombs and blocks preserving information onto the conduit processes that strongly control the dynamics of these events. {A}fter 84 years of repose, a new cycle of eruptive activity of {T}ungurahua volcano ({E}cuador) started in {O}ctober 1999, consisting of recurrent low-to-moderate explosive phases, which included sporadic stronger {S}trombolian to sub-{P}linian pulses, as well as {V}ulcanian outbursts. {T}he 1 {F}ebruary 2014 eruption was one of the most important {V}ulcanian events and was characterized by highly energetic explosions resulting from a plug conduit failure that generated a similar to 9 km-high eruptive column and fallback pyroclastic density currents. {F}our different types of blocks and bombs were found in the deposits of the pyroclastic density currents: dense fragments ({DB}), breadcrust bombs ({BCB}), cauliflower bombs ({CFB}) and foliated, banded bombs ({FB}). {A}ll the different types of bombs have homogenous andesitic bulk-rock compositions but different, highly evolved matrix glass compositions ranging from rhyolitic for {BCB} to dacitic for {CFB} and {DB}, suggesting the occurrence of contrasting shallow crystallization processes within the conduit. {T}he wide variability of the bombs in terms of patterns of surface cracks, external morphologies, internal density and vesicularity gradients records different conditions of formation from a same magma composition.{T}he combination of morphological measurements, compositional data and textural analysis allow us (i) to infer the pre-eruption physical and rheological state of the conduit plug, (ii) to reconstruct the short-scale lateral and vertical gradients characterizing the plug, and (iii) to clarify the specific mechanism controlling the formation conditions of {CFB}, still poorly defined in the literature.},
  keywords = {{V}ulcanian eruption ; {B}readcrust bombs ; {C}auliflower bombs ; {T}ungurahua ; volcano ; {EQUATEUR}},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {444},
  numero = {},
  pages = {107961 [18 ]},
  ISSN = {0377-0273},
  year = {2023},
  DOI = {10.1016/j.jvolgeores.2023.107961},
  URL = {https://www.documentation.ird.fr/hor/fdi:010088910},
}