Ominous San Andreas Fault Study: Risk Of A Big Quake 5X Higher Than Previously Thought

On July 4, 2019, Californians were preparing for a typical festivity — fireworks, barbeques, pool parties — when their homes started to shake. Stress on fault lines near Ridgecrest, Calif. had become too much, and the fault slipped.

Ruptures along three separate lines caused a 6.4 magnitude quake, one of the strongest California has felt in recent years.

Soon, aftershocks with magnitudes hitting between 3.5 and 4.6 followed. California Governor Gavin Newsom declared a state of emergency for the town of Ridgecrest in the Mojave Desert.

Then on Friday, July 5, four separate faults ruptured in the same area, creating a 7.1 magnitude quake — the biggest to hit California in two decades.

Structure fires caused by the quakes engulfed one home in flames, and 15 people were taken to emergency rooms for their injuries. Shaking from the quake was felt everywhere from Sacramento to Tijuana.