How many times has Mt. Vesuvius erupted since 79 AD?

September 8, 2007 9:24 PM

How many times has Mt. Vesuvius erupted since AD 79?

Different sources I've looked at have different answers--more than 50 times, almost 3 dozen times, 29 times, at least 21 times. Does anyone have an authoritative source for an answer? Is a definitive answer even known?

posted by phoenixy to grab bag (4 answers total)

According to Britannica online, confirmed eruptions post-79 A.D. took place in 203, 472, 512, 787, 968, 991, 999, 1007, and finally 1036. After this came a multi-century dormant period, then a series of earthquakes followed by an eruption in late 1631 presaged a new chapter in the volcano's behavior:

After 1631 there was a change in the eruptive character of the volcano and activity became continuous. Two stages could be observed: quiescent and eruptive. During the quiescent stage the volcano's mouth would be obstructed, whereas in the eruptive stage it would be almost continually open. Between 1660 and 1944 some 19 of these cycles were observed. Severe paroxysmal eruptions, concluding an eruptive stage, occurred in the years 1660, 1682, 1694, 1698, 1707, 1737, 1760, 1767, 1779, 1794, 1822, 1834, 1839, 1850, 1855, 1861, 1868, 1872, 1906, and 1944. The eruptive stages varied in length from 6 months to 30¾ years. The quiescent stages have varied from 18 months to 7½ years.

By this reckoning, that would total nine discrete eruptions in the post-Pompeii era, then the reawakening of 1631, followed by 19 eruptive periods ending in '44. (Note that the article specifies "confirmed" eruptions. In addition, the change in behavior after 1631 — with the potential for multiple eruptions during these active periods — probably accounts for the discrepancies you've found in your research.)
posted by rob511 at 9:52 PM on September 8, 2007

Wikipedia.
posted by iamabot at 10:06 PM on September 8, 2007

National Geographic (September 2007) "Vesuvius Countdown"--article begins on page 114.
posted by Womanscientist at 6:41 AM on September 9, 2007

The NG article is here.
posted by thecjm at 1:38 PM on September 9, 2007