Focal mechanism, or beachball diagram, indicating the magnitude-4.2 earthquake under Lake Tahoe had right-lateral strike-slip motion, similar to the San Andreas Fault. Credit: USGS

Focal mechanism, or beachball diagram, indicating the magnitude-4.2 earthquake under Lake Tahoe had right-lateral strike-slip motion, similar to the San Andreas Fault. Credit: USGS

Focal mechanism, or beachball diagram, indicating the magnitude-4.2 earthquake under Lake Tahoe had right-lateral strike-slip motion, similar to the San Andreas Fault. Credit: USGS

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