continued to rebuild and grow. As for Esfahan, it has never suffered a major quake and might be viewed as the country’s safest city And then there’s Tehran, which seismologists consider long overdue for a killer quake.
Thre were nine major earthquakes in Iran in the 20th Century—major defined as a magnitude of 7.1 or greater or a death toll exceeding 2,500.
The death toll figures as well as the magnitude calculations are subject to considerable dispute even in the 20th Century. For earlier quakes, there is even more dispute. But there were about 10 super-quakes in the thousand years before the 20th Century.
The Tehran area has been largely immune to major quakes for a thousand years—but it lies on a major fault line. No serious damage has been recorded in the capital since March 27, 1830, when a quake centered in the Demavand area killed a few dozen Tehranis and cracked many buildings.
Tehran has only been the capital for two centuries and wasn’t notable before that. But Rey, now a mere district of Tehran, was for centuries a major way stop on the Silk Road. Historians in Rey have recorded a number of quakes, but the last super-quake struck February 23, 958, and is estimated to have been about 7.7 on the Richter Scale.
A thousand years is a long time for an area of major seismic activity to go without a major earthquake.
Tabriz is the major urban center that has taken the worst punishment over the years. The city was virtually destroyed three times over.
• In 1402, possibly 40,000 people died in a quake of 7.6 magnitude.
• In 1721, a quake struck southeast of the city, doing modest damage to structures but killing 40,000 persons. It had an estimated magnitude of 7.7.
• In 1780, a major quake of 7.7 struck again, destroying the city and imposing an immense death toll variously estimated at 50,000 to 200,000.
The figures in this article are taken from a technical volume, A History of Persian Earthquakes, written by N.N. Ambraseys and C. P. Melville, civil engineers at Imperial College in London. The book was published by the Cambridge University Press in 1982.
The worst hit city was probably Neyshabur, southwest of Mashhad. It was leveled three times in three centuries. Each quake was estimated at 7.6. The first demolished Neyshabur in 1209, the second in 1389 and the third in 1405.
The city was rebuilt after the first pair of quakes. But residents gave up after the third and Mashhad became the regional city of import.
Shiraz has been hit by one major earthquake—a May 5, 1853, shake of 6.2 intensity that did major damage and killed about 9,000 Shirazis.
Of Iran’s five modern urban areas—Tehran, Tabriz, Mashhad, Shiraz and Esfahan—only Esfahan lies in an area that has never suffered significant seismic activity. Esfahan can be said to be the only safe metropolis in Iran.
In the modern era, and perhaps in all time, the most deadly earthquake in the world is believed to have been the one that struck Tangshan, China, on July 28, 1976. The Chinese government says 242,000 persons died, but independent estimates are all much higher, with the highest figure at 800,000. The magnitude of about 8.0 on the Richter Scale is very high but by no means the record.