The three largest events were the M7.2 thrust mainshock Catastrophe that struck Attack near the unincorporated community of Petrolia midday on April 25 and two primary strike-slip aftershocks Catastrophe measuring 6.5 and 6.6 that followed early the next morning .

As the largest earthquake in California since the 1989 Loma Prieta event several years earlier , the mainshock caused Causation a non-destructive tsunami Catastrophe that quickly reached Arriving the coast , and eventually Alaska and Hawaii several hours later .

Due to the remote location of the mainshock Catastrophe and a series of strong aftershocks Catastrophe , damage Damaging to man made Action structures was limited Limiting to a few cabins close to the areas of the highest intensity .