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Topics: Pyroclastic Volcanic Volcanology Material Geology Surge...

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Pyroclastic flowPyroclastic flows are a common and devastating result of some volcanic eruptions. They are fast moving fluidized bodies of hot gas, ash and rock (collectively known as tephra) which can travel away from the vent at up to 150 km/h. The gas is usually at a PyroclasticPyroclastic is a term used in volcanology to describe air fall material ejected during a volcanic eruption. This material, known as pyroclast may include pumice, volcanic bombs, ignimbrite and ash. See also Pyroclastic flow Pyroclastic rock Pyroclastic su Pyroclastic rockPyroclastic rocks are formed from lavas which are ejected into the air, as occur in pyroclastic flows or Plinian eruptions. They include pumice, volcanic bombs, ignimbrite and ash. The airborne fragments themselves are called pyroclasts (often abbreviated Pyroclastic surgeA pyroclastic surge is a fluidized mass of turbulent gas and rock fragments which is ejected during some volcanic eruptions. It is similar to a pyroclastic flow but contains a much higher of proportion of gas to rock, which makes it more turbulent and all