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Plinian eruption An explosive volcanic eruption of pyroclastic ejecta forming an eruption column which may be up to 55 km high, dispersing ejecta over an area of 500–5000 km2. The eruption column has the distinctive, spreading, branched shape of the stone pine (Pinus pinea) native to the Mediterranean region. A Plinian eruption may produce thick, airfall, pumice deposits, or the eruption column may collapse to generate a pyroclastic flow. This type of eruption is named after Pliny the elder, who died at Pompeii in AD79 during the eruption of Vesuvius that destroyed the city.
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