Research into deadly Italian earthquakes of 2016 can improve future seismic predictions



The timing and scale of three fatal earthquakes that hit Italy in 2016 may have been predetermined, according to new research conducted by Northeast experts.

The study led by Durham University and the arrival of the second anniversary of the beginning of the earthquake series could improve future earthquake predictions.

A joint British-Italian team of geologists and seismologists has shown that the clustering of the three earthquakes could be caused by the establishment of a horizontal network of underground errors.

The findings show that although all three earthquakes occurred on the same major error, a number of smaller errors prevented one massive earthquake and also acted as paths for naturally occurring fluids that later caused earthquakes.

The cluster of three earthquakes, called "seismic series" by seismologists, each had a magnitude of more than six and killed more than 300 people in the Italian Apennines between August 24 and October 30, 2016.

The study published in the journal Earth and Planetary Science Letters may have broader implications for the study of seismic hazards, allowing scientists to better understand potential earthquake sequences after an earthquake.

Dr. Richard Walters, assistant professor at the earth sciences department, Durham University, said: "These results relate to a long-standing mystery in earthquake science – why a large error system sometimes fails in a single major earthquake that tears the entire length, compared to the failure of several smaller earthquakes that have occurred over months or years.

"Our results imply that, although we could not have predicted when the earthquake series would begin, we may have determined in advance both the magnitude and the timing of the major earthquakes by the preparation of errors at depth.

"This is all information that we could hypothetically know before the event, and therefore this could be a hugely important opportunity to improve future earthquake predictions."

Dr. Walters and the team used satellite data to estimate which part of the error failed in every earthquake and compared this pattern with the location and timing of thousands of small aftershocks throughout the seismic series.

They discovered that intersections of minor errors with the main interference system separated each of the three largest earthquakes, which strongly indicates that these intersections stop the growth of any earthquake and prevent errors from failing in one big event.

But in addition, the scientists also discovered that after the first earthquake, thousands of aftershocks went north along the same fracture crossings at a rate of about 100 meters per day, in a manner consistent with the naturally occurring water and gas pumped along the faults by the first earthquake on August 24, 2016.

The second earthquake, on October 26, happened exactly when these liquids reached the site, controlling the relative timing of failure.

Dr. Walters added: "It was a big surprise that these relatively small mistakes had such an enormous influence on the whole series.

"They stop the first earthquake in its tracks, and then they channel the liquids that re-start the series months later – no one has ever seen this before. & # 39;

Co-author Dr. Laura Gregory, at the School of Earth and Environment, at the University of Leeds, UK, said it was important to understand whether a failure in a seismic series fails and whether the results of the team were only possible by combining a varied offer of different datasets.

The study was partially supported by the UK's Natural Environment Research Council, through an emergency and center for the observation and modeling of earthquakes, volcanoes and tectonics (COMET).


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