All of Iran lies within a major earthquake zone, and the country has suffered terrible temblors before most recently in 2003, when a 6.8-magnitude quake leveled the ancient city of Bam and killed more than 30,000 people. But a similar quake in the congested capital of Tehran where more than 7 million people live would be a shattering catastrophe. Unlike building codes in other endangered cities such as San Francisco and Tokyo, Tehran's are relatively lax, and many residents live in the sort of unreinforced-concrete houses that turn into death traps in the event of a strong quake. The Iranian Health Ministry once estimated that a 7-magnitude quake would destroy 90% of the city's hospitals. Tehran is so threatened that there has been periodic talk about moving the capital.
Where Will the Next Five Big Earthquakes Be?
Quakes can't be predicted with the same accuracy as the weather, but a look at global fault lines and the geologic record suggests some places are due for a rumble