I would say that earthquakes are the most challenging of natural disasters. We have absolutely no way of knowing exactly where or when one is going to strike. They can cause destruction through liquefaction, landslides and direct shaking. They can create tsunamis which wash ashore and wipe out enormous areas. In urban areas, secondary effects like fires from broken gas mains, loss of water and sewage infrastructure can cause enormous problems. What happens if no one in Los Angeles can flush their toilet? Things get bad.
