Alberto Carpinteri & Giuseppe Lacidogna 
Earthquakes and Acoustic Emission [PDF ebook] 
Selected Papers from the 11th International Conference on Fracture, Turin, Italy, March 20-25, 2005

Earthquakes are caused by the sudden release of energy during the fracture of stressed rock within the Earth’s crust. This phenomenon is similar to that which occurs in materials under load, and although they take place on very different scales, these two phenomena — earthquakes in geophysics and damage in structural materials — have similarities.