1962 Bou'in-Zahra earthquake
Encyclopedia
The 1962 Bou'in-Zahra earthquake occurred on September 1, 1962, in the area of Bou'in-Zahra, Qazvin Province
, Iran
. 12,225 fatalities resulted from the massive, magnitude 7.1 earthquake
.
Qazvin Province lies in an area of Iran that experiences large earthquakes. The 1962 event originated on one of many faults in the area, called the Ipak Fault. Believed to have been reactivated multiple times, the fault is extensive and could still pose a threat to locals.
Iran's building codes, renowned for performing poorly during earthquakes, were recently evaluated by multiple world organizations. Most hope that the Iranian government will implement a better quality of design, highlighting that Iran is among the most seismically active countries in the world.
Eurasian
and Arabian Plate
s. With both strike-slip and reverse faults, it experiences earthquakes in groups. This indicates that the two types of faults in the country correspond with one another; if one fault is overwhelmed by movement, the movement will branch off to another fault.
Bou'in-Zahra county lies within a zone of active thrust fault
s, complemented by folds
. This zone extends south from the Alborz
mountains. Despite the presence of faults, Qazvin Province
does not regularly experience earthquakes. In fact, the earthquake rate is lower than the national amount. However, the space between earthquakes allows pressure to build up on faults, increasing the power - and magnitude - of the earthquakes.
Specifically, the 1962 event originated on the Ipak Fault of northern Iran. A feature that, with its connected, smaller faults, extends for 64 miles (103 km), it runs from the village of Ipak to Takhrijin. After the earthquake, roughly 64 miles (103 km) of west-northwest trending surface faulting was visible, ripped up by the main quake and aftershocks.
The Ipak Fault is at least as old as the Carboniferous
period, and has probably been reactivated several times since its formation. For this theory, Manuel Berberian
presents various examples. On the fault's south side, Carboniferous material is visible; this debris is not evident on the north side. This is perhaps evident of an aged fault that was present as early as the Carboniferous period, acting as a "dividing fault" while the area around it underwent sedimentation. This odd possibility lead Berberian to pursue study further. He could find no trace of Upper Guadalopian or Julfian sediments north of the fault, either. Another possible reason for this anomaly could be erosion
; uplift
could have exposed the northern portion of the fault but not the south.
s and rock falls occurred posterior to the rupture. 21,000 houses were destroyed, mainly because they were made up of mud and brick. Over 7,500 were buried in 31 individual villages, followed by reports from 60 additional villages. In these villages, however, 26,618 survived. One hospital in Tehran was "packed" with over 2,500 victims.
Slight damage was experienced in Tehran
, the nation's capital. Cities as far away as Tabriz
, Esfahan and Yazd
reported the tremor. Sandblows
also formed along the rupture zone. The earthquake was also declared the largest rupture in the region since approximately 1630, over 300 years prior. Earthquake lights were also sighted from the Rudak area multiple times.
Rescue operators suggested that an aerial and on-land search should be initiated to help victims. Some officials believed that people had gone for over a week with no aid.
Iranian wrestling star Gholamreza Takhti
gathered blankets, money, and food for victims and transported them by trucks.
Marcello Di Cintio mentions the earthquake in his book Poets and Pahlevans: A Journey Into the Heart of Iran. He notes that, because government response was slow, students at the University of Tehran
took matters into their own hands. After gathering supplies, the students organized an effort to dispatch medical students and interns to the site of the disaster. Their teams were however blocked by Iranian National Guard members who had been commanded to kill any civilians who tried to help victims; Di Cintio cites that the "Shah was not about to let a crowd of students draw attention to his inept relief efforts".
in Bou'in-Zahra killed more than 250 people and left roughly 25,000 without homes.
In addition to its geological threat, Iran has poor earthquake engineering
. In a 2004 report, it was listed as "the worst offender" globally for poor earthquake engineering
. Professor Roger Bilham of the University of Colorado at Boulder
, a geophysicist who specializes in earthquake-related deformation and hazards, blames construction practices for the fact that since the start of the 20th century, 1 in 3,000 Iranians has died in an earthquake-related incident. Bilham adds, "Most of Iran needs rebuilding. If the population of Iran had a choice between spending oil revenues on munitions or houses that won't kill them, I suspect they would choose a safe home. It's all a matter of earthquake education." A Common Country Assessment by The United Nations for Iran has similar results, stating that, "While adequate building regulations exist for large cities, it is generally believed that they are not rigorously adhered to... most of those who have suffered in recent major earthquakes have lived in small towns and villages. Earthquake-proof construction is very rare in those areas and adequate building regulations are not yet in place".
Qazvin Province
The Qazvin Province is one of the 31 provinces of Iran. It is in the north-west of the country, and its center is the city of Qazvin. The province was created in 1993 out of part of Tehran Province and includes 20 cities: Qazvin, Takestan, Abyek, Buin-Zahra, Eqhbalieh, Mohammadieh, Alvand,...
, Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
. 12,225 fatalities resulted from the massive, magnitude 7.1 earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
.
Qazvin Province lies in an area of Iran that experiences large earthquakes. The 1962 event originated on one of many faults in the area, called the Ipak Fault. Believed to have been reactivated multiple times, the fault is extensive and could still pose a threat to locals.
Iran's building codes, renowned for performing poorly during earthquakes, were recently evaluated by multiple world organizations. Most hope that the Iranian government will implement a better quality of design, highlighting that Iran is among the most seismically active countries in the world.
Geology
Iran is an earthquake center of the world, lying between the convergingConvergent boundary
In plate tectonics, a convergent boundary, also known as a destructive plate boundary , is an actively deforming region where two tectonic plates or fragments of lithosphere move toward one another and collide...
Eurasian
Eurasian Plate
The Eurasian Plate is a tectonic plate which includes most of the continent of Eurasia , with the notable exceptions of the Indian subcontinent, the Arabian subcontinent, and the area east of the Chersky Range in East Siberia...
and Arabian Plate
Arabian Plate
The Arabian Plate is one of three tectonic plates which have been moving northward over millions of years and colliding with the Eurasian Plate...
s. With both strike-slip and reverse faults, it experiences earthquakes in groups. This indicates that the two types of faults in the country correspond with one another; if one fault is overwhelmed by movement, the movement will branch off to another fault.
Bou'in-Zahra county lies within a zone of active thrust fault
Thrust fault
A thrust fault is a type of fault, or break in the Earth's crust across which there has been relative movement, in which rocks of lower stratigraphic position are pushed up and over higher strata. They are often recognized because they place older rocks above younger...
s, complemented by folds
Fold (geology)
The term fold is used in geology when one or a stack of originally flat and planar surfaces, such as sedimentary strata, are bent or curved as a result of permanent deformation. Synsedimentary folds are those due to slumping of sedimentary material before it is lithified. Folds in rocks vary in...
. This zone extends south from the Alborz
Alborz
Alborz , also written as Alburz, Elburz or Elborz, is a mountain range in northern Iran stretching from the borders of Azerbaijan and Armenia in the northwest to the southern end of the Caspian Sea, and ending in the east at the borders of Turkmenistan and Afghanistan...
mountains. Despite the presence of faults, Qazvin Province
Qazvin Province
The Qazvin Province is one of the 31 provinces of Iran. It is in the north-west of the country, and its center is the city of Qazvin. The province was created in 1993 out of part of Tehran Province and includes 20 cities: Qazvin, Takestan, Abyek, Buin-Zahra, Eqhbalieh, Mohammadieh, Alvand,...
does not regularly experience earthquakes. In fact, the earthquake rate is lower than the national amount. However, the space between earthquakes allows pressure to build up on faults, increasing the power - and magnitude - of the earthquakes.
Specifically, the 1962 event originated on the Ipak Fault of northern Iran. A feature that, with its connected, smaller faults, extends for 64 miles (103 km), it runs from the village of Ipak to Takhrijin. After the earthquake, roughly 64 miles (103 km) of west-northwest trending surface faulting was visible, ripped up by the main quake and aftershocks.
The Ipak Fault is at least as old as the Carboniferous
Carboniferous
The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...
period, and has probably been reactivated several times since its formation. For this theory, Manuel Berberian
Manuel Berberian
Manuel Berberian is an Iranian geologist and a Member of NY Academy of Sciences.His origin is from Armenian ethnic-religious minority of Diarbakr in east of Turkey who forced to migrate to Iran after 1915-Armenian massacre.-Career:...
presents various examples. On the fault's south side, Carboniferous material is visible; this debris is not evident on the north side. This is perhaps evident of an aged fault that was present as early as the Carboniferous period, acting as a "dividing fault" while the area around it underwent sedimentation. This odd possibility lead Berberian to pursue study further. He could find no trace of Upper Guadalopian or Julfian sediments north of the fault, either. Another possible reason for this anomaly could be erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
; uplift
Tectonic uplift
Tectonic uplift is a geological process most often caused by plate tectonics which increases elevation. The opposite of uplift is subsidence, which results in a decrease in elevation. Uplift may be orogenic or isostatic.-Orogenic uplift:...
could have exposed the northern portion of the fault but not the south.
Damage and casualties
12,225 fatalities resulted from the earthquake. An additional 2,776 people were injured; along with 21,310 houses either destroyed or too damaged to repair. 35 percent of domestic livestock was also killed, and several landslideLandslide
A landslide or landslip is a geological phenomenon which includes a wide range of ground movement, such as rockfalls, deep failure of slopes and shallow debris flows, which can occur in offshore, coastal and onshore environments...
s and rock falls occurred posterior to the rupture. 21,000 houses were destroyed, mainly because they were made up of mud and brick. Over 7,500 were buried in 31 individual villages, followed by reports from 60 additional villages. In these villages, however, 26,618 survived. One hospital in Tehran was "packed" with over 2,500 victims.
Slight damage was experienced in Tehran
Tehran
Tehran , sometimes spelled Teheran, is the capital of Iran and Tehran Province. With an estimated population of 8,429,807; it is also Iran's largest urban area and city, one of the largest cities in Western Asia, and is the world's 19th largest city.In the 20th century, Tehran was subject to...
, the nation's capital. Cities as far away as Tabriz
Tabriz
Tabriz is the fourth largest city and one of the historical capitals of Iran and the capital of East Azerbaijan Province. Situated at an altitude of 1,350 meters at the junction of the Quri River and Aji River, it was the second largest city in Iran until the late 1960s, one of its former...
, Esfahan and Yazd
Yazd
Yazd is the capital of Yazd Province in Iran, and a centre of Zoroastrian culture. The city is located some 175 miles southeast of Isfahan. At the 2006 census, the population was 423,006, in 114,716 families....
reported the tremor. Sandblows
Sand volcano
A sand volcano or sand blow is a cone of sand formed by the ejection of sand onto a surface from a central point. The sand builds up as a cone with slopes at the sand's angle of repose. A crater is commonly seen at the summit...
also formed along the rupture zone. The earthquake was also declared the largest rupture in the region since approximately 1630, over 300 years prior. Earthquake lights were also sighted from the Rudak area multiple times.
Relief efforts
Iranian wrestling star Gholamreza Takhti
Gholamreza Takhti
Gholamreza Takhti is the most famous wrestler in Iranian history. He was most famous for his chivalrous behavior and sportsmanship, and he continues to symbolize the essence of sport to the Iranian people.- Early life :...
gathered blankets, money, and food for victims and transported them by trucks.
Marcello Di Cintio mentions the earthquake in his book Poets and Pahlevans: A Journey Into the Heart of Iran. He notes that, because government response was slow, students at the University of Tehran
University of Tehran
The University of Tehran , also known as Tehran University and UT, is Iran's oldest university. Located in Tehran, the university is among the most prestigious in the country, and is consistently selected as the first choice of many applicants in the annual nationwide entrance exam for top Iranian...
took matters into their own hands. After gathering supplies, the students organized an effort to dispatch medical students and interns to the site of the disaster. Their teams were however blocked by Iranian National Guard members who had been commanded to kill any civilians who tried to help victims; Di Cintio cites that the "Shah was not about to let a crowd of students draw attention to his inept relief efforts".
Future threats
As roughly 90 percent of Iran lies within seismically active land, the threat from earthquakes is high. In 2002, an earthquake2002 Bou'in-Zahra earthquake
The 2002 Bou'in-Zahra earthquake occurred on June 22, 2002 in a region of northwestern Iran which is crossed by several major fault lines. The earthquake's epicenter was near the city of Bou'in-Zahra in Qazvin Province, an area known for destructive earthquakes...
in Bou'in-Zahra killed more than 250 people and left roughly 25,000 without homes.
In addition to its geological threat, Iran has poor earthquake engineering
Earthquake engineering
Earthquake engineering is the scientific field concerned with protecting society, the natural and the man-made environment from earthquakes by limiting the seismic risk to socio-economically acceptable levels...
. In a 2004 report, it was listed as "the worst offender" globally for poor earthquake engineering
Earthquake engineering
Earthquake engineering is the scientific field concerned with protecting society, the natural and the man-made environment from earthquakes by limiting the seismic risk to socio-economically acceptable levels...
. Professor Roger Bilham of the University of Colorado at Boulder
University of Colorado at Boulder
The University of Colorado Boulder is a public research university located in Boulder, Colorado...
, a geophysicist who specializes in earthquake-related deformation and hazards, blames construction practices for the fact that since the start of the 20th century, 1 in 3,000 Iranians has died in an earthquake-related incident. Bilham adds, "Most of Iran needs rebuilding. If the population of Iran had a choice between spending oil revenues on munitions or houses that won't kill them, I suspect they would choose a safe home. It's all a matter of earthquake education." A Common Country Assessment by The United Nations for Iran has similar results, stating that, "While adequate building regulations exist for large cities, it is generally believed that they are not rigorously adhered to... most of those who have suffered in recent major earthquakes have lived in small towns and villages. Earthquake-proof construction is very rare in those areas and adequate building regulations are not yet in place".