Afghanistan is considered as a country prone to a
number of natural disasters: earthquakes, flooding, drought, landslides, and
avalanches. Earthquakes are relatively frequent, being more frequent in
the north and northeast, and often trigger landslides. Afghanistan is geologically
located in the active part of the world where two tectonic plates, the Iranian
Plate and the Eurasian Plate, meet. The Indian plate (northward-moving) is
colliding with the southern part of the Eurasian plate at a rate of about 1.7
inches per year. Both the Iranian Plate and the Eurasian Plate consists of continental
crust, which can neither sink nor be destroyed. Since Afghanistan is sitting on
a collision plate boundary, it has created some of the world's highest
mountains and causes slips on major faults that generate large and often
devastating earthquakes. Every few years, a powerful earthquake takes place in
Afghanistan and causes significant damage and fatalities in the war torn
country where there is poor transport and communications. Modern seismograph
networks show that earthquake activity is widespread throughout much of the
eastern part of the country. In addition to the damage caused by strong
shaking, earthquakes can trigger destructive landslides, especially in
mountainous terrain, which is very common in much of northeastern Afghanistan.
Earthquakes also cause damage from liquefaction, where water-saturated soil
becomes unstable and liquefies, and from ground subsidence, where shaking
causes shifting and settlement of the ground surface.
As Afghanistan’s infrastructure is rebuilt and
modernized and its natural resources developed, critical facilities and major
construction projects need to be located and designed to take into account the
potential adverse effects of natural hazards such as earthquakes. A lot of the
earthquakes that take place in Afghanistan may not be massive but the lack of warning
system, building codes, and preventive measures increase the number of
casualties. Buildings/houses are built without any codes and a lot of times, in
the rural regions, a lot of the locals build their own houses using mostly mud.
Earthquakes don’t necessarily kill a lot of people but the high death tolls usually
come from unsuitable building constructions. Proper design of such facilities and
structures will help ensure that Afghanistan’s new and reconstructed
infrastructure is durable enough to survive the impact of major earthquakes,
which will inevitably occur.
Researchers with the
USGS Earthquake Hazards Project compiled extensive data on the location, size,
and frequency of past earthquakes in Afghanistan, and examined satellite and
aerial imagery to identify the locations of potentially active faults. This
information was then used to create preliminary earthquake hazard maps that
show the strength of probable ground motion caused by earthquakes at specific
localities and nationwide. The level of ground motion is expressed as a percent
of the acceleration due to the force of gravity (% g), which is a parameter
that engineers often use as a guide in designing structures such as hospitals,
dams, pipelines, and power transmission lines.
Every year, thousands of people die in Afghanistan
from various natural disasters, but earthquake results massive destruction of
building and human losses in the Easter region of the country such as Takhar
and Badakhshan. Also, houses are usually made of mud by locals, and therefore,
even minor quake results vast fatalities and destruction. Also, houses are poorly
built in the mountain skirts of Hindu Kush where any minor earthquake could
cause a vast destruction and casualties. In order to prevent Eastern area from
injuries, construction of homes should be strictly limited and people should be
informed about the hazards of active faults since they are not aware of the
danger. Moreover, building codes in this area should require structures that
framed in wood, steel, or have appropriately reinforced concrete, but
construction of masonry walls made of bricks, concrete blocks, stone, and mud
should be prohibited. Load bearing masonry walls of any kind are likely to
shake apart and collapse during an earthquake, dropping heavy roofs on people
indoors. House can be built to withstand severe earthquakes well enough to
minimize the risk to people inside. Even if a properly frames buildings is
severely damaged, it’s unlikely to collapse. Reinforced concrete often breaks
in large earthquakes, leaving the formerly enclosed reinforcing steel free to
buckle and fail.
Earthquakes are more frequent in the north and
northeast and, therefore, the safest place where I would live would be in the
southwest region of the country such as Kandahar, Helmand and Nimruz.
Yes, this area reminds me very much to what happened in Nepal. Lots of really bad constructions in areas of risk...I know in Nepal; at least they 'marked' the unsafe houses after the first big quake this year, and people were not allowed in those anymore. So when the second one hit, nobody in those houses died (by the way those house were absolutely destroyed in the second quake). It is good to see the reinforcements in housing are happening. Thank you for showing us this country this semester!
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