Cahuilla, pronounced /kəˈwiːə/, (formerly, Kawia, Coahuilla, Cohuilla, and Coahuila)[2] is an unincorporated community in Riverside County, California.

The strongest one occurred in August 2018, south of Lake Riverside, just off Cahuilla Road (SR 371).

By using computer algorithms, researchers were able to piece together a detailed picture of the Cahuilla fault zone responsible for the earthquake swarm.

Containing complex subterranean horizontal channels and prominent bents in its depth profile, the fault zone sits on top of a deeper natural underground reservoir of fluid under pressure with a connector at 8 km (5.0 mi) below the surface that was initially sealed off from the fault zone.

When that seal broke open in early 2016, fluids were injected up into the fault zone's base and diffused slowly through the complex channels up to 5 km (3.1 mi) below the surface, which triggered the prolonged earthquake swarm that lasted until late 2019.