Short Plinian eruptions can end in less than a day, but longer events can take several days to months. The longer eruptions begin with production of clouds of volcanic ash, sometimes with pyroclastic flows. The amount of magma erupted can be so large that the top of the volcano may collapse, resulting in a caldera. Fine ash can deposit over large areas. Plinian eruptions are often accompanied by loud noises, such as those generated by Krakatoa.
Plinian eruptions, also known as 'Vesuvian eruptions', are volcanic eruptions marked by their similarity to the eruption of Mount Vesuvius in AD 79 and is named after Pliny the Elder who who got killed in that cataclysmic event.
Plinian eruption of Mt Redoubt