Three earthquakes measuring over 6 on the Richter scale have hit Italy in the span of a little over two months, killing 297 people in the 6.2 August quake. On October 30, another destructive 6.6 earthquake battered central Italy, devastating the historic Basilica of St. Benedict. Now a seismologist from an Italian national institution said there could be more quakes in a process akin to a ‘domino effect.’
Seismologist Gianluca Valensise of the National Institute for Geophysics and Vulcanology in Italy told Reuters, “An earthquake measuring 6 or larger creates stresses that are redistributed across adjacent faults and can cause them to rupture, and this is probably what we have seen since August. This process can continue indefinitely, with one big quake weakening a sister fault in a domino process that can cover hundreds of kilometers, in principle.”
Italy has seen processes similar to the domino effect before. In 1783, Southern Italy experienced five earthquakes that measured 6.5 or higher in under two months. In 1997, two earthquakes struck central Italy over two days and about 20 days after still another hit, with small ones scattered in between. Valensise said the 2016 earthquake sequence thus far is “on a larger scale” than in 1997.
On August 24, a 6.2 earthquake rattled central Italy. This past week the region saw a 6.1 earthquake on Wednesday, and a 6.6 earthquake on Sunday. Valensise said the August earthquake is connected to the others through a “geodynamic link.”
He can’t predict whether or not there will be more large quakes in central Italy this year, but said there will certainly be aftershocks for “at least a few weeks.” But since fault lines to the southeast and northwest of the beleaguered central region have been hit lately, according to Valensise, “if the process of stress redistribution finds other faults close to rupture level they could go off in the next days or weeks.”