Ten Key Points

1. Mount Vesuvius is a stratovolcano, meaning it is made up of many layers (strata) of hardened lava and ash.
2. Vesuvius' 79 AD eruption covered both Pompeii and Herculaneum with ash.
3. The eruption was caused by the collision of two tectonic plates: African and Eurasian.
4. Pliny the Younger, an eyewitness who recorded the event, coined the term "Plinian."
5. The area experienced foreshock earthquakes in 62AD, 64AD as well as frequently in the four days prior to the eruption.
6. The eruption released 4km cubed of ash and rock composed of leucite and phonolite.
7. Phase one of the eruption, lasted approximately twenty hours and deposed up to 2.8 meters of pumice.
8. Phase two of the eruption consisted of deadly rock and hot gas in a pyroclastic flow.
9. 38% of the 1,150 bodies are thought to have been killed by roof collapses and falling rocks, while the other 62% have been found in pyroclastic surge deposits killed by inhalation of ash and blast debris.
10. The eruption changed local topography, specifically the course of the Sarno River.