If you've experienced an earthquake then you problem know what's coming when you start to feel that shaking and hear the rumbling. This week on Science on the Radio, Dr Marvin Druger takes a look at the science behind this natural diaster. What areas of the country are most susceptible to earthquakes? What equipment is used to measure the size of an earthquake? And how big would an earthquake need to be for you to actually feel the plates shifting? Hear the answers to those questions and more