@article{fdi:010082128,
  title = {{M}ulti-parametric field experiment links explosive activity and persistent degassing at {S}tromboli},
  author = {{T}hivet, {S}. and {H}arris, {A}. {J}. {L}. and {G}urioli, {L}. and {B}ani, {P}hilipson and {B}arnie, {T}. and {B}ombrun, {M}. and {M}archetti, {E}.},
  editor = {},
  language = {{ENG}},
  abstract = {{V}isually unattainable magmatic processes in volcanic conduits, such as degassing, are closely linked to eruptive styles at the surface, but their roles are not completely identified and understood. {T}o gain insights, a multi-parametric experiment at {S}tromboli volcano ({A}eolian {I}slands, {I}taly) was installed in {J}uly 2016 focusing on the normal explosive activity and persistent degassing. {D}uring this experiment, gas-dominated (type 0) and particle-loaded (type 1) explosions, already defined by other studies, were clearly identified. {A} {FLIR} thermal camera, an {U}ltra-{V}iolet {SO}2 camera and a scanning {D}ifferential {O}ptical {A}bsorption {S}pectroscopy were deployed to record pyroclast and {SO}2 masses emitted during individual explosions, as well as persistent {SO}2 fluxes, respectively. {A}n {ASHER} instrument was also deployed in order to collect ash fallouts and to measure the grain size distribution of the samples. {SO}2 measurements confirm that persistent degassing was far greater than that emitted during the explosions. {F}urther, we found that the data could be characterized by two periods. {I}n the first period (25-27 {J}uly), activity was mainly characterized by type 0 explosions, characterized by high velocity jets. {P}yroclast mass fluxes were relatively low (280 kg/event on average), while persistent {SO}2 fluxes were high (274 t/d on average). {I}n the second period (29-30 {J}uly), activity was mainly characterized by type 1 explosions, characterized by low velocity jets. {P}yroclast mass fluxes were almost ten times higher (2,400 kg/event on average), while persistent gas fluxes were significantly lower (82 t/d on average). {A}sh characterization also indicates that type 0 explosions fragments were characterized by a larger proportion of non-juvenile material compared to type 1 explosions fragments. {T}his week-long field experiment suggests that, at least within short time periods, {S}tromboli's type 1 explosions can be associated with low levels of degassing and the mass of particles accompanying such explosive events depends on the volume of a degassed magma cap sitting at the head of the magma column. {T}his could make the classic particle-loaded explosions of {S}tromboli an aside from the true eruptive state of the volcano. {I}nstead, gas-dominated explosions can be associated with high levels of degassing and are indicative of a highly charged (with gas) system. {W}e thus suggest that relatively deep magmatic processes, such as persistent degassing and slug formation can rapidly influence the superficial behavior of the eruptive conduit, modulating the presence or absence of degassed magma at the explosion/fragmentation level.},
  keywords = {particle size distribution ; persistent degassing ; pyroclast mass flux ; real-time monitoring ; strombolian explosions ; explosive degassing ; ash ; characterization ; {ITALIE} ; {STROMBOLI}},
  booktitle = {},
  journal = {{F}rontiers in {E}arth {S}cience},
  volume = {9},
  numero = {},
  pages = {669661 [17 ]},
  year = {2021},
  DOI = {10.3389/feart.2021.669661},
  URL = {https://www.documentation.ird.fr/hor/fdi:010082128},
}