| Eruption of Mount Vesuvius in AD 79 | |
|---|---|
Computer-generated imagery of the Mount Vesuvius eruption |
|
| Volcano | Mount Vesuvius |
| Date | AD 79 |
| Type | Plinian, Peléan |
| Location | Naples, Italy |
| VEI | 5 |
| Impact | Obliterated the Roman settlements of Pompeii and Herculaneum |
In the year of AD 79, Mount Vesuvius erupted in one of the most catastrophic and famous eruptions of all time. The Roman vicinities of Pompeii, Herculaneum and Stabiae were affected,[1] and Pompeii and Herculaneum were obliterated.[1][2] Mount Vesuvius spawned a deadly cloud of stones, ash and fumes to a height of 20.5 miles, spewing molten rock and pulverized pumice at the rate of 1.5 million tons per second, ultimately releasing a hundred thousand times the thermal energy released by the Hiroshima bombing.[2][3]
Since systematic excavations began in Pompeii in 1860, excavators have uncovered within the city limits the petrified-ash shells of the decomposed bodies of 40 victims.[3] Historians discovered that the vicinity was obliterated by pyroclastic flows.[3][4] Pliny the Younger, a Roman administrator and poet, was the author of an account of the eruption, which was successful in rendering its nature.[4]
Pliny the Younger authorized an account of the eruption —
Broad sheets of flame were lighting up many parts of Vesuvius; their light and brightness were the more vivid for the darkness of the night... it was daylight now elsewhere in the world, but there the darkness was darker and thicker than any night.[5]
An estimated 16,000 citizens in the Roman vicinities of Pompeii and Herculaneum perished due to hydrothermal pyroclastic flows at temperatures up to 700 °C (1292 °F).[6][7][8] A precursor, the Avellino eruption in the Bronze Age, deposited about 0.32 km3 of white pumice ("the white pumice phase"), while a second, more intense explosion raised a column of 31 km (102,000 ft) depositing 1.25 km3 of grey pumice ("the grey pumice phase");[9] however, the 79 eruption produced a rain of pumice southward of the cone that built up to depths of 2.8 metres (9 ft 2 in) at Pompeii.
The eruption of Vesuvius in 79 unfolded in two phases,[10] a Plinian eruption that lasted eighteen to twenty hours, followed by a pyroclastic flow or nuée ardente in the second, Peléan phase that reached as far as Misenum but was concentrated to the west and northwest. Two pyroclastic flows engulfed Pompeii, burning and asphyxiating the stragglers who had remained behind. Oplontis and Herculaneum received the brunt of the flows and were buried in fine ash and pyroclastic deposits.
Stratigraphic studies of the eruption were compared to the eruption of the Bronze Age and allegations of a possible future disaster were put forward.[11] Since the eruption of 1944, Vesuvius has been relatively silent; however, it was theorized that the longer it remains silent, the worse the eruption, especially a danger to the densely populated area around the volcano.[12]