The Wilmington fault...is an elusive type of fracture. Unlike many faults, which crack Earth’s surface like an egg, the Wilmington fault is “blind,” which means it’s concealed beneath the surface, making it especially difficult to study. So while scientists have long known the fault is present—stretching 12.4 miles under southern Los Angeles into San Pedro Bay—it was presumed to have sat quiet for millions of years. While the fault is slow moving and likely ruptures only once every 3,200 to 4,700 years, it underlies two of the United States’ busiest ports. And researchers worry that the Wilmington could link with...
