Earthquakes are sudden and intense shaking of the ground caused by the movement of tectonic plates or volcanic activity. They can occur anywhere in the world and have the potential to cause significant damage to buildings, infrastructure, and loss of life. Seismologists study earthquakes to understand their causes and predict future events, but predicting the exact timing and location of an earthquake remains a challenge.
Now they do. The Northwestern research team of seismologists and statisticians has developed an earthquake probability model that is more comprehensive and realistic than what is currently available. Instead of just using the average time between past earthquakes to forecast the next one, the new model considers the specific order and timing of previous earthquakes.
However, “Large earthquakes don’t occur like clockwork,” Neely said. “Sometimes we see several large earthquakes occur over relatively short time frames and then long periods when nothing happens. The traditional models can’t handle this behavior.” “Earthquake clusters imply that faults have long-term memory,” said Salditch, now at the U.S. Geological Survey. “If it’s been a long time since a large earthquake, then even after another happens, the fault’s ‘memory’ sometimes isn’t erased by the earthquake, leaving left-over strain and an increased chance of having another. Our new model calculates earthquake probabilities this way.”