“This process can continue indefinitely, with one big quake weakening a sister fault in a domino process that can cover hundreds of kilometres, in principle,” Gianluca Valensise, a seismologist at Italy’s National Institute for Geophysics and Vulcanology, told The Sydney Morning Herald. Stress redistribution in the fault network then led to the subsequent two quakes. The first in the current cluster of quakes – a magnitude 6.2 which killed nearly 300 people – broke two neighbouring faults known as Laga and Vettore. These small mountain faults move apart at an average rate of around 3mm per year, but the movement occurs in fits and starts, as the recent quakes demonstrate. The Apennine mountain chain is made up from a network of small faults (around 10 to 20km long) which stretch open and help accommodate the movement of the big plates colliding. Magma from that blast has been found in Greenland, some 4,500 km away.Italy sits on the boundary between the African and Eurasian tectonic plates, with the African plate diving down beneath the Eurasian plate, just to the east of Italy. One of its biggest eruptions took place some 39,000 years ago and might have led to the extinction of Neanderthal man, researchers say. The Campi Flegrei caldera has a diameter of about 12-15 km (7.5-9.3 miles) and last erupted in 1538. state of Wyoming but of more concern because they are in an area populated by around 3 million people in the Naples hinterland.įILE PHOTO: Mount Vesuvius is seen covered by snow, in Naples, Italy February 14, 2018. The Campi Flegrei are similar to the Yellowstone caldera in the U.S. A local official said his recommendation was being reviewed. There was no sign of structural damage in the area after Wednesday's tremor.ĭe Natale confirmed a report in Corriere Della Sera newspaper that he had written to the government last week suggesting possible evacuations. He said if there was an eruption, it would be a phreatic, or steam-blast eruption - which are generally relatively weak and devoid of new magma - at least initially. WATCH: How the evolution of land plants helped to shape Earth SEE ALSO: Is Canada prone to a devastating earthquake? Answer isn't so simpleĮxperts say there is no imminent threat of an eruption, but Giuseppe De Natale, the former head of the Vesuvius observatory at the National Institute for Geophysics and Volcanology (INGV), called for urgent checks on buildings after repeated seismic activity that is pushing up the ground by 1.5 cm (0.59 inches) a month. However, it is a much bigger volcano than Vesuvius and if it ever exploded at full force could kill millions. ROME (Reuters) - A leading volcanologist has warned that mass evacuations might be needed in a town close to Naples, which sits on a so-called Super Volcano that has been hit by hundreds of small earthquakes in recent weeks.Ī 4.2 magnitude earthquake struck the area early on Wednesday, the strongest jolt in 40 years to rattle the volcanic field, known as the Campi Flegrei or Phlegraean Fields from the Greek word for burning.ĬampiFlegrei sits across the bay of Naples from Pompeii, where thousands were incinerated by Mount Vesuvius in 79 AD.
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