When you think about a natural disaster, you might think of a sudden and dramatic event like a tornado, earthquake, tsunami, or an explosion. But you might not think of the many small and gradual changes that lead up to a major event. It's these changes that are the most important to understand to prepare for the worst.

A large earthquake can cause a large difference in ground level, and if it's big enough, it can cause a significant amount of damage, even if it happens in a remote area. It's these events that are most likely to cause an earthquake.