Tuesday, 16 April 2013

Magnitude 7.8 Earthquake in southeast Iran; high level of casualties expected.

Slightly before 4.45 pm local time (10.45 am GMT) on Tuesday 16 April 2013, the southeast of Iran was hit by a Magnitude 7.8 Earthquake at a depth of 82 km, close to the border with Pakistan and roughly 86 km east of the city of Khash, according to the United States Geological Survey. This is a remote area with a sparse population, but this is a severe quake and will have been felt over a wide area, so the level of casualties is expected to be high; at the time of writing 81 fatalities have been reported. The quake was felt as far away as New Deli, 1500 km to the east.

The location of the April 16 Earthquake. Google Maps.

Iran is situated on the southern margin of the Eurasian Plate. Immediately to the south lies the Arabian Plate, which is being pushed northward by the impact of Africa from the south. This has created a zone of faulting and fold mountains along the southwest coast of the country, known as the Zagros Thrust Belt, while to the northeast of this the geology is dominated by three large tectonic blocks, the Central Iran, Lut and Helmand, which move separately in response to pressure from the south, stretching and compressing the rock layers close to the surface and creating frequent Earthquakes, some of which can be very large.

The geological stresses on, and tectonic units of, Iran. Mahdavifar et al. (2002).

The population of Iran is particularly at risk from Earthquakes as, unlike other Earthquake-prone nations, very few buildings in the country are quake-resistant. The majority of residential buildings in Iran are made of mud-brick, a building material particularly vulnerable to Earthquakes as the bricks often liquify, trapping people inside and quickly asphyxiating them with dust. This is particularly dangerous at night when the majority of people are inside sleeping, but it is to be hoped that this quake, which occurred in the late afternoon has caused less casualties than some historic nighttime quakes.

Survivors of the quake searching for lost relatives. One India.


Follow Sciency Thoughts on Facebook.