There is much to know about volcanoes and their eruptions before we can fully dissect the events of AD 79.  Vesuvius is a stratovolcano, which are usually tall, mountainous volcanoes whose steep sides have been formed over time by repeated deposits of ash, lapilli, lava, and pyroclastic flows.  Other types of volcanoes, such as the shield, cinder cone, and lava dome volcanoes, produce very different types of eruptions.

Vesuvius’ eruption in AD 79 was named a Plinian eruption, since Pliny was the first to document its shape and characteristics.  Plinian eruptions are characterized by the pine-tree-shaped clouds that form above the volcano’s crater, as well as the wide variety of hazardous materials ejected by the volcano (such as ash, poisonous gases, and lapilli).

These eruptions occur when the vast plates beneath the Earth collide and send heated material—in the form of magma—through weak spots in the Earth’s crust.  Vesuvius sits on the edge of the Eurasian plate, which is in constant collision with the African plate, resulting in a great deal of volcanic activity.  Indeed, Vesuvius erupted as recently as 1944, and in order to provide advance warnings for any impending eruptions, its geologic activity is monitored around the clock.

Continue to the phases of the eruption >>