Precariously balanced rocks provide clues for unearthing underground fault connections
Stacked in gravity-defying arrangements in the western San Bernardino Mountains, near the San Andreas Fault, granite boulders that should have been toppled by earthquakes long ago resolutely remain. In exploring why these rocks still stand, researchers have uncovered connections between Southern California’s San Jacinto and San Andreas faults that could change how the region plans for future earthquakes.