Volcanogenic

12 items found. Page 1 of 2.

Volcanogenic

GH0012

Pyroclastic Density Current

Pyroclastic density currents are hot, fast-moving mixtures of volcanic particles and gas that flow according to their density relative to the surrounding medium and the Earth’s gravity. They typically originate from the gravitational collapse of explosive eruption columns, lava domes or lava-flow fronts, and from explosive lateral blasts (adapted from Branney and Kokelaar, 2002 and Cole et al., 2015).

Volcanogenic

GH0013

Debris Flow/Lahars/Floods

Lahars are discrete, rapid, gravity-driven, water-saturated flows containing water and solid particles of volcanic rock, sediment, ice, wood, and other debris that originate at volcanoes (Gudmundsson, 2015; Vallance and Iverson, 2015).

Volcanogenic

GH0014

Landslide (Volcanic Trigger)

A landslide is the downslope movement of soil, rock and organic materials under the effects of gravity, which occurs when the gravitational driving forces exceed the frictional resistance of the material resisting on the slope. Landslides could be terrestrial or submarine (Varnes, 1978).

Volcanogenic

GH0015

Ground Shaking (Volcanic Earthquake)

Ground shaking is the movement of the Earth’s surface from earthquakes. Ground shaking is produced by waves that travel through the earth and along its surface (USGS, no date).

A volcanic earthquake is any earthquake that results from tectonic forces which occur in conjunction with volcanic activity (UN-SPIDER, no date).

Volcanogenic

GH0016

Volcanic Gases and Aerosols

Volcanic gas includes any gas-phase substance that is emitted by volcanic or volcanic-geothermal activity. Volcanic aerosols include liquid or solid particles that are small enough to be suspended in the air, and that are emitted by volcanic or volcanic-geothermal activity (adapted from Baxter and Horwell, 2015, Fischer and Chiodini 2015, and Williams- Jones and Rymer 2015).

Volcanogenic

GH0017

Tsunami (Volcanic Trigger)

Volcano tsunamis (pronounced soo-ná-mees), are a series of waves created when water surrounding a volcano is displaced following an eruption, a landslide, or failure of a volcanic edifice into surrounding water. If the generating mechanism is large enough, the waves can be significant on local, regional or even transoceanic scales (Day, 2015).

Volcanogenic

GH0018

Lightning (Volcanic Trigger)

Volcanic lightning is an electrical discharge caused by a volcanic eruption. It is typically associated with ash-rich eruption plumes but can also arise from a range of volcanic processes including ground-hugging ash flows and lava-ocean entry (adapted from Mather and Harrison, 2006; Behnke and McNutt, 2014; and McNutt and Thomas, 2015).

Volcanogenic

GH0019

Urban Fire (During/Following Volcanic Eruption)

Urban fires are fire involving buildings or structures in cities or towns with potential to spread to adjoining structures. Triggers of urban fires are numerous, from human actions (e.g., knocking over a candle) and technological triggers (e.g., power surge overloading appliances), to natural triggers (e.g., wildland fires interacting with urban areas). Triggers from volcanic eruptions include lava flows, pyroclastic density currents, tephra, and ground shaking (adapted from Baxter et al., 2005 and ISO, 2020).

Volcanogenic

GH0009

Lava Flows (Lava Domes)

A lava flow or lava dome is a body of lava that forms during an eruption, or main eruptive episode. Lava flows are outpourings of fluid, relatively low-viscosity molten rock, whereas a lava dome is a pile of relatively viscous lava that cannot flow far from the vent (Calder et al., 2015; Kilburn, 2015).

Volcanogenic

GH0020