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Density Stratification and Buoyancy Evolution in Pyroclastic Density Currents
Journal of Geophysical Research: Solid EarthAbstractPyroclastic density currents (PDCs) are density‐stratified along their vertical axis, with the near‐bed portion being denser than the upper portion, resulting from particle settling and ambient air entrainment at current margins. Whereas vertical density stratification likely influences mixing, sedimentation, and buoyancy of PDCs, many depth ...
Sean B. O’Donnell +6 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.
A. Bevilacqua
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Generation of Overspill Pyroclastic Density Currents in Sinuous Channels
Journal of Geophysical Research: Solid Earth, 2021AbstractDue to their mobility, high velocities, and common occurrence, small‐volume pyroclastic density currents (PDCs) represent a major hazard around volcanoes. Small‐volume events are particularly sensitive to topography and channelization into drainage basins. Understanding the flow transition initiated by avulsion or overspill from valley confined
A. Kubo Hutchison, J. Dufek
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Geological Society, London, Special Publications, 1998
Abstract High-speed, gravity-driven flows of hot particles and gas are a common and highly destructive product of explosive volcanism. They range widely in nature from expanded, turbulent suspension currents formed by lateral blasts or by the fountaining of vertical eruption columns, to highly concentrated granular avalanches ...
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Abstract High-speed, gravity-driven flows of hot particles and gas are a common and highly destructive product of explosive volcanism. They range widely in nature from expanded, turbulent suspension currents formed by lateral blasts or by the fountaining of vertical eruption columns, to highly concentrated granular avalanches ...
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Erosional characteristics and behavior of large pyroclastic density currents
Geology, 2012Factors influencing the erosive behavior of large pyroclastic density currents (PDCs), both mainly massive and thinly stratified, are not well understood. To investigate the parameters influencing the erosive behavior of PDCs produced during the flowing phase of large, caldera-forming Plinian (Campanian Ignimbrite) and phreatoplinian (Neapolitan Yellow
SCARPATI, CLAUDIO, Perrotta A.
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Generation of air lubrication within pyroclastic density currents
Nature Geoscience, 2019Pyroclastic density currents are highly dangerous ground-hugging currents from volcanoes that cause >50% of volcanic fatalities globally. These hot mixtures of volcanic particles and gas exhibit remarkable fluidity, which allows them to transport thousands to millions of tonnes of volcanic material across the Earth’s surface over tens to hundreds of ...
Gert Lube +6 more
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The Fluid Mechanics of Pyroclastic Density Currents
Annual Review of Fluid Mechanics, 2016Pyroclastic density currents are generated in explosive volcanic eruptions when gas and particle mixtures remain denser than the surrounding atmosphere. These mobile currents have a diversity of flow regimes, from energetic granular flows to turbulent suspensions.
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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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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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