Scientists have discovered a new fault zone along the coast of Southern California that could lead to a devastating tsunami at some point.

The alarming finding would mean that these geological fractures could result in an earthquake that could measure 8.0 on the Richter scale, which would send giant waves smashing into the coast and hammered Los Angeles and San Diego, according to a SlashGear report.

The study was published in the Journal of Geophysical Research: Earth Surface by geologists who wanted to examine two active transpressional fault zones via high-resolution mapping. The scientists knew about the Santa Cruz-Catalina Ridge fault as well as the Ferrelo fault, but they wanted to take new depth measurements to take a more detailed look at the crust and what changes it had undergone.

Geologists were alarmed to find that there was evidence of multiple segments that could rupture over a distance greater than 100 kilometers. One of the tectonic plates would suddenly shift up if that rupture were to occur, leading to a big earthquake and a massive displacement of water that could lead to devastating results for Southern California.

And it’s not unheard of to have such an earthquake, according to Mark Legg, a geologist who was the lead author of the study, according to the report. He pointed out that there have been earthquakes of at least a magnitude of 7.0 offshore.

It’s not a reason to panic just yet, but Legg noted it’s an indication that Southern California residents need to understand that tsunamis are a very real possibility in that part of the world and to be prepared as a result.