@article{fdi:010091002,
  title = {{D}ifferent physics but similar dependence of runout distance with discharge rate : the duality of pyroclastic density currents},
  author = {{R}oche, {O}livier and {A}zzaoui, {N}. and {G}uillin, {A}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e address emplacement mechanisms of pyroclastic density currents ({PDC}s) through relationships between their runout distance and mass discharge rate of their parent eruptions. {A}ssuming axisymmetric propagation typical of dilute currents that are little controlled by topography, we apply a simple method to estimate the runout distance of concentrated {PDC}s channelized in valleys. {W}ith these data, the runout distance of concentrated currents varies, as for their dilute counterparts, with the discharge rate to the power similar to 0.5, the latter being the consequence of radial propagation of the currents. {T}his simple dependence between runout distance and discharge rate is both surprising and remarkable considering the fundamentally different natures of dilute or concentrated {PDC}s, which are governed by complex physics involving many parameters. {T}his dependence further suggests that particle settling velocity, which controls the rate of decrease of the flow mass, has a second-order effect on the runout distance. {W}e argue that the hindered settling model established for particle suspensions in a static fluid is relevant for estimating the settling velocity of particles in concentrated {PDC}s. {S}ettling velocities of similar to 0.1 to 10 cm/s calculated for some natural examples correspond to deposit aggradation rates of the same order. {T}hese rates imply timescales of deposit formation significantly shorter than flow durations in some cases, suggesting that onset of deposition occurs at late stages of emplacement.},
  keywords = {{P}yroclastic density currents ; {D}ischarge rate ; {R}unout distance ; {P}ower law relationship ; {P}article hindered settling ; {D}eposit aggradation},
  booktitle = {},
  journal = {{B}ulletin of {V}olcanology},
  volume = {86},
  numero = {7},
  pages = {65 [14 ]},
  ISSN = {0258-8900},
  year = {2024},
  DOI = {10.1007/s00445-024-01750-8},
  URL = {https://www.documentation.ird.fr/hor/fdi:010091002},
}