Seismicity

Iran is one of the most seismically active countries in the world due to ninety percent of the country crossing over several major fault lines. It is positioned in a 1000- km- wide zone of compression between the colliding Eurasian and Arabian continents. From 1918- 2004, more than 2000 earthquakes were recorded in Iran. Most earthquakes in the continental lithosphere take place in the upper crust. Continental collision creates a shortening in the crust, resulting in thickening and distributed deformation. In the Zagros Mountains, nearly all earthquakes have a depth less than 20 kilometers (km) since they take place in the upper crust; this is where earthquakes occur the most frequent. On the other hand, in Southeastern Iran, where the Arabian seafloor is subducted beneath the Makran coast, low- level earthquakes occur from the upper crust to depths of at least 150 kilometers. Close to the Oman line, between Zagros and Makrain, seismicity reaches to depths of 30 to 45 km in the crust. In North- Central Iran, along the Aborz mountain belt, there is seismic activity in both the upper and lower crust, although mostly upper. The band across central Caspian consists of earthquakes with depths of 30 to 100 kilometers that deepen northwards. From the early 1900's to the late 1990's, there has been many earthquakes with a magnitude higher than 7. For example, in 1978 quake Tabas consisted of a 7. 7 magnitude which is highly destructive. Luckily, the Zagro's region has not faced any in the 20th century with a magnitude higher than 7.0. But earthquakes with magnitudes over 7.0 have shocked Central and Eastern Iran. Unfortunately, these earthquakes have been catastrophic and lead to the loss of human life and wide spread damage. 
 Due to the devastating earhtquake, Bam, the U.S. offered assistance in return the state promised to comply with the International Atomic Energy Agency. Iran agreed with the U.S. and focused on rebuilding their country. Testing, analyzing, and other methods were used by scientists, as well, to monitor activity. For example, the seismic hazard assessment of Iran was created by the International Institute of Earthquake Engineering and Seismology so that it could indicate the earthquakes hazard of Iran.

Works Cited:
Geofisica, Annali. "Seismic Hazard Assessment of Iran." International Institution of Earthquake  Engineering and Seismology. Vol 42, N. 6. 6 December, 1999. Web. 18 Feb 2016.

"Relocation and Assessment of Seismicity in the Iran Region." Geophys. J. Int. 4 April. 2006. Web. 18 Feb 2016.