@article{fdi:010068356,
  title = {{T}he controls and consequences of substrate entrainment by pyroclastic density currents at {M}ount {S}t {H}elens, {W}ashington ({USA})},
  author = {{P}ollock, {N}. {M}. and {B}rand, {B}. {D}. and {R}oche, {O}livier},
  editor = {},
  language = {{ENG}},
  abstract = {{E}vidence in the deposits from the {M}ay 18, 1980 eruption at {M}ount {S}t {H}elens demonstrates that pyroclastic density currents ({PDC}s) produced during the afternoon of the eruption became intermittently erosive. {U}sing detailed componentry and granulometry we constrain the sources for lithic blocks in the deposits and identify deposits from {PDC}s that became locally erosive. {T}he componentry of the lithics in the fall deposits is used as a proxy for vent erosion and assumed to represent the starting componentry for {PDC}s prior to entrainment from any other source. {W}e find little evidence in the {PDC} deposits nearest to the base of the volcano for entrainment from the steep flanks; however, significant evidence indicates that {PDC}s eroded into the debris avalanche hummocks, suggesting that entrainment is favored as {PDC}s interact with highly irregular topography. {E}vidence for locally entrained material downstream from debris avalanche hummocks decreases with height in the outcrop, suggesting that less entrainment occurs as local relief decreases and upstream topography is buried. {T}he prevalence of lithofacies containing locally entrained material at the base of unit contacts and only 10s of meters downstream from debris avalanche hummocks suggests that the majority of entrainment occurs at or near the head of the current. {O}ccasionally, entrained material is located high above unit contacts and deposited well after the initial head of the current is inferred to have passed, indicating that entrainment can occur during periods of non-deposition either from the semi-sustained body of the current or from a pulsating current. {A}dditionally, self-channelization of {PDC}s, either by levee deposition or scouring into earlier {PDC} deposits, occurs independently of interaction with topographic obstacles and can affect carrying capacity and runout distance. {W}hile we begin to explore the mechanisms and effects of erosion on current dynamics, additional laboratory and numerical studies are necessary to fully understand these processes.},
  keywords = {{P}yroclastic density current ; {M}ount {S}t {H}elens ; {E}rosion ; {B}ulking ; {T}opography ; {S}elf-channelization ; {ETATS} {UNIS}},
  booktitle = {},
  journal = {{J}ournal of {V}olcanology and {G}eothermal {R}esearch},
  volume = {325},
  numero = {},
  pages = {135--147},
  ISSN = {0377-0273},
  year = {2016},
  DOI = {10.1016/j.jvolgeores.2016.06.012},
  URL = {https://www.documentation.ird.fr/hor/fdi:010068356},
}