"Earthquake in Turkey was an earthquake doublet"

Luca Dal Zilio. (Photograph: ETH Zurich) ETH Zurich researcher Luca Dal Zilio offers an insightful summary of the recent earthquakes in Turkey and Syria, shedding light on the complex nature of this event. He discusses the lessons that can be drawn from it to better understand and prepare for future seismic occurrences in the region. by Peter Rüegg ETH News: You and your colleague Jean-Paul Ampuero from Geoazur have just published a commentary on the early February earthquakes in Turkey in a scientific journal. What's new? - Luca Dal Zilio: The two powerful earthquakes that hit Turkey and Syria on 6 February 2023 were of similar magnitude (7.8 and 7.6) and only nine hours apart. These events are referred to as an earthquake doublet because they are a pair of powerful earthquakes that have centroids closer than their rupture size and occur within a time frame that is shorter than the recurrence time inferred from the plate motion. There was long talk of an exceptionally strong aftershock. The second earthquake in this case wasn't a typical aftershock, as it was almost as strong as the first one and occurred on a different, nearby fault. According to Bath's Law, the largest aftershock is usually about 1.2 magnitudes smaller than the main earthquake. A series of earthquakes like the recent events in Turkey and Syria has its own unique features. Studying these events helps us learn more about earthquakes and improves our ability to predict them. Why did an earthquake doublet occur?