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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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Geology, 2011
AbstractThe Plinian columns formed during the magmatic phase of the A.D. 79 eruption of Vesuvius alternated several times between fully stable, buoyantly rising regimes and unstable regimes of partial or total collapse. Six pyroclastic density currents (PDCs) were produced during unstable regimes, and ultimately caused the destruction of Roman towns ...
Shea, Thomas +4 more
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AbstractThe Plinian columns formed during the magmatic phase of the A.D. 79 eruption of Vesuvius alternated several times between fully stable, buoyantly rising regimes and unstable regimes of partial or total collapse. Six pyroclastic density currents (PDCs) were produced during unstable regimes, and ultimately caused the destruction of Roman towns ...
Shea, Thomas +4 more
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Effects of topography on pyroclastic density current runout and formation of coignimbrites
Geology, 2011Laboratory experiments of dilute mixtures of warm talc powder in air simulate dilute pyroclastic density currents (PDCs) and show the effects of topography on current runout, buoyancy reversal, and liftoff into buoyant plumes. The densimetric and thermal Richardson, Froude, Stokes, and settling numbers for our experiments match those of natural PDCs ...
Benjamin J. Andrews, Michael Manga
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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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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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A laboratory study of plumes associated with pyroclastic density currents
Volcanic plumes associated with propagating pyroclastic density currents can rise tens of kilometers into the atmosphere, dispersing fine ash particles over large areas with a potential hazard for aviation safety. Such plumes originate from the buoyancy reversal of the pyroclastic density currents caused by the entrainment and heating of ambient air ...Guillaume Carazzo, Geoffrey Robert
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Monitoring of Eruptive Products: Pyroclastic Density Currents and their Deposits
2022Pyroclastic density currents (PDCs) are a mixture of gases and solid particles that move across the Earth's topography under the influence of gravity. The term PDC has been proposed by several authors over the past 30 years in an effort to describe a natural continuum between two end-members: dilute currents, in which the fluid is prevalent, and ...
Tadini, Alessandro +4 more
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Dynamics and hazards of stratified pyroclastic density currents
2014In the context of a study on pyroclastic flow hazards in caldera settings, we have analyzed the role of particle sedimentation and stratification on the kinematics of particle-driven gravity currents. By means of a two-dimensional multiphase flow numerical model we have simulated the propagation of monodisperse particle-laden currents triggered by the ...
Esposti Ongaro , Tomaso +3 more
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Insights into Acoustic Sources from Pyroclastic Density Currents
Pyroclastic Density Currents (PDCs) are deadly, highly destructive, fast-moving, ground-hugging, mixtures of hot gas and volcanic particles. PDC high velocities, dynamic pressures, and temperatures make direct field measurements extremely challenging.Anna Perttu +5 more
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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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