On May 10, 1997, an earthquake measuring 7.1 on the Richter magnitude scale, hit Northern Iran, the Khorasan Province. The earthquake, known as the Qayen earthquake, was centered approximately 270 kilometres south of Mashhad on the village of Ardekul and was by far the biggest to have happened in the area since 1990. With a death toll of 1567 and over 2300 casualties, that was the third earthquake in 1997 to have caused so much damage and devastation in the Birjand-Qayen region. 50000 are homeless and over 15000 homes and 57 villages were destroyed or damaged. 155 aftershocks, measuring 5.5 on the Richter magnitude scale, also resulted in a rise in the death toll. Many of the aftershocks occurred along the rupture reaching 24 kilometres below the surface. Sources differ on whether the Qayen earthquake was caused by the left lateral or the right lateral movement. There was a low amount of stress drop, evidence that some slip faulting occurred. The maximum horizontal acceleration was approximately 6.9 metres per second (nearly three-quarters of the acceleration an object would have in free-fall) and occurred near the earthquake's epicentre. The crustal layer involved in the rupture was 20 to 25 meters thick. The surface fault that caused the earthquake extended for 110 kilometres, which was longer than expected given the earthquake's magnitude. The Qayen earthquake had an estimated damage of $100 million.
Many countries responded by donating neccesities such as food, clothing, etc. Rescue teams were also there to assist local volunteers in finding survivors trapped under debris. The damage caused by the Qayen earthquake was attributed to poor construction practices and changes in building codes. The earthquake was the first major earthquake since the year 1979. As suggested by one expert, a country-wide rebuilding program will be needed to address ongoing public safety concerns. (http://en.wikipedia.org/wiki/1997_Qayen_earthquake, http://www.amazines.com/1997_Qayen_earthquake_related.html, http://ci.nii.ac.jp/naid/110002674231/en)
Many countries responded by donating neccesities such as food, clothing, etc. Rescue teams were also there to assist local volunteers in finding survivors trapped under debris. The damage caused by the Qayen earthquake was attributed to poor construction practices and changes in building codes. The earthquake was the first major earthquake since the year 1979. As suggested by one expert, a country-wide rebuilding program will be needed to address ongoing public safety concerns. (http://en.wikipedia.org/wiki/1997_Qayen_earthquake, http://www.amazines.com/1997_Qayen_earthquake_related.html, http://ci.nii.ac.jp/naid/110002674231/en)
