@article{fdi:010068272,
  title = {{T}he milling factory : componentry-dependent fragmentation and fines production in pyroclastic flows},
  author = {{B}ernard, {J}. and {L}e {P}ennec, {J}ean-{L}uc},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n order to decipher the mobility of hazardous small-volume pyroclastic flows ({PF}s), we investigate here the role of clast fragmentation and production of fine particles (<2 mm) in controlling {PF} dynamics. {W}e report a high-resolution textural data set (i.e., grain size distribution, clast componentry, and clast morphology) of andesitic scoriaceous {PF} deposits from {T}ungurahua volcano ({E}cuador) based on a unique method and data processing procedure. {T}he strong relationship shown between clast size and componentry in {PF} deposits is quantified through a componentry versus size index ({CSI}), which varies between -1 and +1 (all components in the coarse or fine fractions, respectively). {O}ur results show that the incorporated old lava clasts ({CSI} of -0.33) control early grinding of the pristine juvenile bombs ({CSI} of -1), which produce smaller scoriaceous andesitic fragments ({CSI} of 0.26). {T}hese latter interact in the granular assemblage and release fine particles through the abrasion processes, as supported by the morphological data. {T}he textural maturity of the deposits reveals that the "milling factory" works before sedimentation begins (i.e., on steep upper slopes) and that there is some balance between fines production and loss. {T}he process evident here tends to redistribute stress into the moving flow and produces fines that contribute to fluidization of it. {T}he milling factory is thus likely to enhance the mobility of geophysical flows, which has strong implications for modeling and hazard assessment purposes.},
  keywords = {{EQUATEUR} ; {TUNGURAHUA} {VOLCAN}},
  booktitle = {},
  journal = {{G}eology},
  volume = {44},
  numero = {11},
  pages = {907--910},
  ISSN = {0091-7613},
  year = {2016},
  DOI = {10.1130/g38198.1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010068272},
}