Plinian

Plinian refers to a category of volcanic eruption characterized by sustained, columnar eruption of gas-rich magma, producing tall eruption columns and widespread tephra fall. The term is derived from Pliny the Younger, who described the 79 CE eruption of Mount Vesuvius in his letters to Tacitus, providing the earliest detailed account of a highly explosive eruption. In modern volcanology, a Plinian eruption is defined by a sustained, high-altitude plume that can reach the stratosphere, ejection of pumice and ash, and pressure release through an eruption column rather than discrete explosions. The eruption typically lasts hours to days and can produce pyroclastic surges or flows at the vent's base at times after column fragmentation.

The principal products are ash clouds, pumice and other tephra, with ashfall spread over large distances, sometimes causing global climate effects via volcanic aerosols. The mechanism involves high-viscosity magma with abundant dissolved gases that are rapidly exsolved as pressure is released, fragmenting magma into fine ash and pumice.

In classifications, Plinian eruptions are contrasted with Strombolian and Vulcanian eruptions; VEI scales often place them as high-intensity events (VEI 4–6), with an Ultra-Plinian subclass for exceptionally large eruptions. Plinian activity may be followed by shorter, more violent episodes or transition to other styles as magma supply wanes.

Origin: The name commemorates the account by Pliny the Younger of Vesuvius's AD 79 eruption, though similar episodes occur in other volcanic systems.