Balanced boulders in earthquake country highlight interconnected faults

Precariously balanced boulders look like bizarre accidents in any landscape, but when they’re found in regions famous for frequent earthquakes, such gravity-defying formations are even more improbable. Scientists have long wondered about an odd collection of dozens of balanced boulders in the San Bernardino Mountains that seemingly should have been toppled centuries ago by the earthquakes that regularly shake Southern California. Even stranger, these car- to house-sized granite boulders are located within 10 kilometers of the active San Andreas and San Jacinto faults. Now, new detective work on 36 of the boulders is giving scientists clues about the connections between these faults. 
 

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Mary Caperton Morton

Mary Caperton Morton

Morton (https://theblondecoyote.com/) is a freelance science and travel writer based in Big Sky, Mont., and an EARTH roving correspondent.  

Monday, December 14, 2015 - 06:00