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Pyroclastic Density Currents at Volcán de Colima
2019In the last ~500 years, Volcan de Colima has generated numerous small-volume pyroclastic density currents (PDCs) that have been associated with dome emplacement, either by a partial collapse or by their explosive destruction. Large PDCs were generated by eruption column collapse in 1690, 1818, and 1913.
R. Saucedo +4 more
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Pyroclastic density current invasion maps
2016Campi Flegrei is an active caldera containing densely populated settlements at very high risk of pyroclastic density currents (PDCs). We present here an innovative method for assessing background spatial PDC hazard with probabilistic invasion maps conditional on the occurrence of an explosive event.
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Abrasion in pyroclastic density currents: Insights from tumbling experiments
Physics and Chemistry of the Earth, Parts A/B/C, 2012During granular mass movements of any kind, particles may interact with one another. The degree of interaction is a function of several variables including; grain-size distribution, particle concentration, density stratification and degree of fluidisation. The impact of particle interaction is additionally influenced by the relative speed, impact angle
Ulrich Kueppers +3 more
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A fast, calibrated model for pyroclastic density currents kinematics and hazard
Journal of Volcanology and Geothermal Research, 2016Abstract Multiphase flow models represent valuable tools for the study of the complex, non-equilibrium dynamics of pyroclastic density currents. Particle sedimentation, flow stratification and rheological changes, depending on the flow regime, interaction with topographic obstacles, turbulent air entrainment, buoyancy reversal, and other complex ...
Ongaro, Tomaso Esposti +2 more
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Effects of flow density on the dynamics of dilute pyroclastic density currents
Journal of Volcanology and Geothermal Research, 2004Abstract Dilute turbulent pyroclastic density currents may have densities as large as 10–100 kg m −3 . Laboratory experiments using dense gases show that for such currents, the speed of the head of the current depends on the density difference between the current and the surrounding air in a complex way.
Sarah E. Nield, Andrew W. Woods
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Aeromechanic analysis of pyroclastic density currents past a building
Bulletin of Volcanology, 2013An aeromechanic analysis of pyroclastic density currents (PDCs) past a building is carried out on the results of a computer simulation. The analysis shows that PDCs strongly interact with buildings, resulting in turbulent boundary layer separation and recirculation.
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Hazards from pyroclastic density currents at Mt. Etna (Italy)
Journal of Volcanology and Geothermal Research, 2009Abstract Despite the recent recognition of Mount Etna as a periodically violently explosive volcano, the hazards from various types of pyroclastic density currents (PDCs) have until now received virtually no attention at this volcano. Large-scale pyroclastic flows last occurred during the caldera-forming Ellittico eruptions, 15–16 ka ago, and the ...
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Flow and sedimentation of pyroclastic density currents
2015Our Earth is a living Planet in which rocks are exhumed at the surface, and subjected to erosion, transport and deposition. Pyroclastic density currents (PDCs) concentrate all these steps in a single phenomenon. During explosive volcanic eruptions, rock fragments known as pyroclasts are ejected from the inside of the Earth to the surface. They can then
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Pyroclastic density currents at Ruapehu volcano; New Zealand
2016Pyroclastic density currents (PDCs) are hazardous mixtures of volcanic particles and gas that travel along the flanks of a volcano due to a higher bulk density than the surrounding atmosphere. Understanding the frequencies, magnitudes, and different PDC generation and transport processes is essential for understanding the PDC hazard.
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Dispersal and air entrainment in unconfined dilute pyroclastic density currents
Bulletin of Volcanology, 2014Unconfined scaled laboratory experiments show that 3D structures control the behavior of dilute pyroclastic density currents (PDCs) during and after liftoff. Experiments comprise heated and ambient temperature 20 μm talc powder turbulently suspended in air to form density currents within an unobstructed 8.5 × 6 × 2.6-m chamber.
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