Plinian eruptions are marked by columns of smoke and ash extending high into the stratosphere. The key characteristics are ejection of large amount of pumice and very powerful continuous gas blast eruptions.
Short eruptions can end in less than a day. Longer events can take several days to months. The longer eruptions begin with production of clouds of volcanic ash, optionally 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 heard at Krakatoa.
The examples of large Plinian eruptions resulting in formation of a caldera are the 1883 Krakatoa eruption in Indonesia, the 1980 eruption of Mount St. Helens, the 1815 eruption of Mount Tambora, also in Indonesia, the 1667 & 1739 eruptions of Mount Tarumae in Japan , the 1600 BC Thera eruption, and the 4860 BC eruption that formed the Crater Lake, and of course Vesuvius in AD 79, which was the prototypical Plinian Eruption. The lava is usually rhyolitic and rich on silicates; basaltic lavas are unusual for Plinian eruptions, the example is the 1886 eruption of Mount Tarawera.
Pliny the Elder set out to rescue the victims from their perilous position on the shore of the Bay of Naples, and launched his galleys, crossing the bay to Stabiae (near the modern town of Castellammare di Stabia). Pliny the Younger provided an account of his death, and suggested that he collapsed and died through inhaling poisonous gases emitted from the volcano. His body was found interred under the ashes of the Vesuvius with no apparent injuries on 26 August, after the plume had dispersed, confirming asphyxiation or poisoning.