Fault line behind 2016 quake also caused Rome tremor in AD443
SCIENTISTS believe they have found the fault line that caused an earthquake that damaged the Colosseum and other buildings in Rome 1,500 years ago.
It is the same fault responsible for a powerful quake three years ago that devastated the mountain town of Amatrice and its surrounding villages, killing 300 people.
The fault system is located on Monte Vettore, a mountain in central Italy that is part of the Apennine chain.
Scientists dug trenches around the fault line to expose sediment layers and establish if there had been tectonic shifts in the past that had led to earthquakes.
They discovered that the system had caused major earthquakes roughly every 1,800 years, including one in the 5th century AD.
The researchers matched that event with an earthquake that struck Rome in AD 443, when the Colosseum was damaged as well as a basilica and a number of early churches.
References to the repairs that were done to the buildings are contained in the writings of two emperors, as well as by Pope Leo I, who reigned from AD440 until his death in AD461.
The earthquake was felt as far away as Ravenna on the Adriatic coast, according to chronicles from the fifth century.
The discovery that the fault line on Monte Vettore caused several earthquakes in the past suggests that the 6.2 magnitude Amatrice quake, in August 2016, which was followed by another quake in October, was not as surprising as first thought but part of a well-established pattern.
Other fault lines that are apparently dormant in the Appenines may also erupt into life, the scientists believe.
“In hindsight, one could say that the 2016 earthquake was not so unexpected as previously supposed,” said Paolo Galli, the team leader from Italy’s National Civil Protection Department.
Italy is one of the most seismically active countries in Europe because it lies at the southern edge of the Eurasian tectonic plate where it rubs up against the Adriatic and African plates.
The findings were published in the American Geophysical Union journal Tectonics.