Rare "Boomerang" Earthquake Recorded Along A Fault Line In The Atlantic

Earthquakes are frequent events that happen around the Earth as fault lines break. Sometimes it can lead to catastrophes such as collapsed buildings or tsunamis. Because of the potential for human death, earthquakes are dangerous and are highly studied phenomena. An international team of researchers have recorded what they call a "boomerang" earthquake along the Romanch fracture zone in the Atlantic Ocean.

A boomerang earthquake happens when a ruptured spreads away from the initial break and turns running back the other way and higher speed. The Romanche fracture zone is a fault line that stretches for 900 km under the depths of the Atlantic Ocean. The researchers recorded an earthquake in 2016 that was a magnitude 7.1 along the fracture zone.

The team tracked the rupture along the fault, revealing that initially, the rupture traveled in one direction before turning around midway through the earthquake and breaking the "seismic sound barrier" to become an ultra-fast earthquake. Only a few of this type of earthquake have been recorded globally.

The team says that if a similar earthquake happened on land, a seismic rupture turning around mid-way through an earthquake could significantly increase the amount of ground shaking caused. Before the gathering of the new information, the mechanism had been unaccounted for in earthquake scenario modeling.

The new data could help scientists to find similar patterns in other earthquakes and add new scenarios to their model to improve earthquake forecasting. The data was recorded using the ocean bottom seismometer network. It is a multi-million-dollar experiment that's funded by the Natural Environment Research Council from the UK, the European Research Council, and the National Science Foundation from the US. The goal is to provide some sort of forecasting for earthquakes to help reduce lives lost disaster.