Science: The Mechanism of Earthquakes

Earthquakes seem to happen at random; they seldom give advance warning, and cannot be predicted with any certainty. Last week Professor Hugo Benioff of CalTech explained his theory that all great shallow earthquakes (originating in rock slippage less-than 45 miles below the surface) have a common cause and are released by a single "mechanism."

Geophysicists have long thought that earthquakes are caused by a sudden release of strain (distortion) in the earth's crust. Dr. Benioff studied the records of all major earthquakes since 1904 and made a chart of their "strain-rebound" characteristics. Somewhat to his surprise, the chart made a regular, sawtooth...

Want the full story?

Subscribe Now


Get TIME the way you want it

  • One Week Digital Pass — $4.99
  • Monthly Pay-As-You-Go DIGITAL ACCESS$2.99
  • One Year ALL ACCESSJust $30!   Best Deal!
    Print Magazine + Digital Edition + Subscriber-only Content on

Learn more about the benefits of being a TIME subscriber

If you are already a subscriber sign up — registration is free!