Reconciling pyroclastic flow and surge: the multiphase physics of pyroclastic density currents

Reconciling Pyroclastic Flow and Surge: the Multiphase Physics of Pyroclastic Density Currents

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Geomagnetic paleointensity in historical pyroclastic density currents: Testing the effects of emplacement temperature and postemplacement alteration

Thellier-type paleointensity experiments were conducted on welded ash matrix or pumice from the 1912 Novarupta (NV) and 1980 Mt. St. Helens (MSH) pyroclastic density currents (PDCs) with the intention of evaluating their suitability for geomagnetic paleointensity studies. PDCs are common worldwide, but can have complicated thermal and alteration histories. We attempt to address the role that em...

Experimental study of turbulence, sedimentation, and coignimbrite mass partitioning in dilute pyroclastic density currents

Residential building and occupant vulnerability to pyroclastic density currents in explosive eruptions

A major hazard during the eruption of explosive volcanoes is the formation of pyroclastic density currents (PDCs). Casualties and physical building damage from PDCs are caused by the temperature, pressure, and particle load of the flow. This paper examines the vulnerability of buildings and occupants to the forces imposed by PDCs along with associated infiltration of PDC particle and gas mixtur...

Sedimentology and geomorphology of the deposits from the August 2006 pyroclastic density currents at Tungurahua volcano, Ecuador

The deposits of the pyroclastic density currents from the August 2006 eruption of Tungurahua show three facies associations depending on the topographic setting: the massive, proximal cross-stratified, and distal cross-stratified facies. (1) The massive facies is confined to valleys on the slopes of the volcano. It contains clasts of >1 m diameter to fine ash material, is massive, and interpret...