By Stephen Tames and Mubsar Dhuka
Tectonic fault lines are the most common location for earthquake, though they can occur across much of the world and even deep under water.
The most vulnerable areas are poor and have loose building codes, which causes much more damage from an equally powerful quake.
In poor areas the effects of an earthquake can be devastating, and even in well developed regions quakes can cause massive damage and loss of life.
Vulnerable areas can implement better building codes, and use flexible foundations to protect buildings and lives.
- The average rate of motion across the San Andreas Fault Zone during the past 3 million years is 56 mm/yr (2 in/yr). This is about the same rate at which your fingernails grow. Assuming this rate continues, scientists project that Los Angeles and San Francisco will be adjacent to one another in approximately 15 million years.