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Bradyn Blower's List: GEOL112 EQ essay

    • The loss of life has also been worsened by the structure of most of the buildings in the city. These are made from baked mud bricks which turn to mud and sand when a building collapses- reducing the chances of air pockets existing for buried survivors.
    • Thousands of aid workers from more than 30 countries have flown into Iran to help with rescue work. Efforts are now focusing on providing food, shelter, water and medical treatment for at least 100,000 people left homeless by the quake.

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    • Historical information and all available records show that approximately 130 large earthquakes have taken place in most parts of Iran. Considering the high seismicity of Iran, a comprehensive hazard reduction program was launched in Iran in 1991, but the effectiveness of the measures have been limited by lack of adequate funding and institutional coordination.
    • closer analysis of what transforms a natural event into a human and economic disaster reveals that the fundamental problems of development that the region faces are the very same problems that contribute to its vulnerability to the catastrophic effects of natural hazards. The principal causes of vulnerability in the region include rapid and uncontrolled urbanization, the persistence of widespread urban and rural poverty, the degradation of the region's environment resulting from the mismanagement of natural resources, inefficient public policies, and lagging and misguided investments in infrastructure. Development and disaster-related policies have largely focused on emergency response, leaving a serious underinvestment in natural hazard prevention and mitigation. A proactive stance to reduce the toll of disasters in the region requires a more comprehensive approach that encompasses both pre-disaster risk reduction and post-disaster recovery. It is framed by new policies and institutional arrangements that support effective action.

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    • About 70% of the houses in Bam have been destroyed, Iranian state television reported.
    • Telephones, electricity and water supplies have been cut by the tremor.
    • A study was carried out to assess psychological distress among Bam earthquake survivors and factors associated with severe mental health in those who survived the tragedy.
    • In conclusion the findings from this study indicated that the survivors of Bam earthquake suffer from psychological distress three times higher than the normal population. In addition female gender, lower education, unemployment, and loss of family members were found to be associated with more severe psychological morbidity among survivors. This suggests that to reduce negative health impacts of the earthquake adequate psychological counseling is needed for those who survived the tragedy.
    • A new study by a University of Colorado at Boulder geological sciences professor suggests one earthquake causing up to 1 million fatalities on Earth each century could occur unless more earthquake-resistant construction materials are implemented.
    • In the pre-1600s few city populations exceeded 1 million people, he said. By 1950, there were 43 “supercities” with populations from 2 million to more than 15 million. “Today, there are nearly 200 supercities on Earth, and the number could double before world populations stabilize.” Roughly 8 million people have died globally as a result of building collapses during earthquakes in the past 1,000 years, he said, although the record is sketchy prior to 1600. “But it is clear that a four-fold increase in the annual death toll from earthquakes between the 17th and 20th centuries is linked to increased urbanization.”

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    • Earthquakes don’t kill people, but buildings and builders of inferior buildings do.”


    • A key insight; compare the death tolls from Loma Prieta with those of Kobe, two events of nearly identical magnitude and depth. But one killed over 5,000, and the other killed 63.

    • Using the magnitude 6.6 earthquake that devastated Bam, Iran, in 2003 as a case study, Fielding and his university colleagues analyzed radar images from the European Space Agency's Envisat satellite to study the land surface above a fault that is buried about 1 kilometer (half a mile) under Earth's surface. They discovered a shallow, narrow surface depression that formed and evolved after the quake, which killed more than 30,000 people.
    • The results have implications for assessing the risk of future earthquakes associated with known buried faults, which can be found around the world but are often missed by geologists or assumed not to be active. Buried faults are thought to be responsible for the major 1992 Landers and 1999 Hector Mine earthquakes in Southern California.

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    • It is planned prefabricated shelter, semi-permanent, earthquake resistant housing, common spaces for women and young people, financial assistance for Iranian NGOs working with women and young people, vocational training for young and disabled people, and disaster preparedness and search and rescue training will benefit the population.

       

      A budget of A$ 872 112 has been identified for this work.

    • Water is polluted and at very low pressure – there is no pipe sewage system and 200 emergency washing places with plastic sheeting and roof have been set up.
    • Turkish aid workers were setting up a tent city in neighboring Iran's quake-hit city of Bam on Friday after some 400 tents dispatched from Turkey had reached the quake area.
       The tent city is expected to house 1,500-2,000 people in Bam, an ancient Silk Road city where a powerful earthquake last week killed an estimated 30,000 people and displaced tens of thousands.

    •  Turkey, which shares a border with Iran and is also prone to disastrous earthquakes, has dispatched medical teams and humanitarian supplies to the scene.

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    • This earthquake occurred as the result of stresses generated by the motion of the Arabian plate northward against the Eurasian plate at a rate of approximately 3 cm/yr (about one inch per year). Deformation of the Earth's crust in response to the plate motion takes place in a broad zone that spans the entire width of Iran and extends into Turkmenistan. Earthquakes occur as the result of both reverse faulting and strike-slip faulting within the zone of deformation.
    • Preliminary analysis of the pattern of seismic-wave radiation from the December 26 earthquake is consistent with the earthquake having been caused by right-lateral strike-slip motion on a north-south oriented fault. The earthquake occurred in a region within which major north-south, right-lateral, strike-slip faults had been previously mapped, and the epicenter lies near the previously mapped, north-south oriented, Bam fault. However, field investigations will be necessary to determine if the earthquake occurred on the Bam fault or on another, possibly not yet mapped, fault. The December 26 earthquake is 100 km south of the destructive earthquakes of June 11, 1981 (magnitude 6.6, approximately 3,000 deaths) and July 28, 1981 (magnitude 7.3, approximately 1,500 deaths). These earthquakes were caused by a combination of reverse-motion and strike-slip motion on the north-south oriented Gowk fault.  

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    • Arg-e-Bam  is made entirely of  mud bricks, clay, straw  and the trunks of palm  trees.
    • Birth rate:
              Definition    Field Listing       Rank Order    
          17.23 births/1,000 population (2003 est.)          
      Death rate:
              Definition    Field Listing       Rank Order    
          5.54 deaths/1,000 population (2003 est.)  
    • he Loma Prieta earthquake killed so few people relative to the similar magnitude Kobe quake not only due to its remote location — the Santa Cruz Mountains of California — but because in addition to its remoteness most of the relatively sparse population live in wood-frame homes which are very effective in resisting catastrophic damage from earthquakes.  Even so, a number of homes closely adjacent to the slipping portion of the San Andreas Rift fell flat that day.  Reportedly, accelerations from the Loma Prieta quake in the immediate vicinity of the San Andreas equaled earth's gravity but in a horizontal direction!  It's hard for most any home or structure to resist that.
      • The Loma Prieta earthquake was one of the costliest natural disasters in U.S. history.  The earthquake occurred in the remote Santa Cruz Mountains and caused severe damage in San Francisco and Oakland, 50 miles north of the end of the fault segment that slipped. 

          
           
        • Deaths: 62
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        • Injuries: 3,757
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        • Damage: more than $6 billion
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        • San Francisco Bay bridge unusable for 1 month
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        • Number of homes damaged: 18,306
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        • Number of business damaged: 2,575
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        • Persons displaced: 12,053
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        BUT… What will happen when an earthquake of similar magnitude occurs close to these population centers? 

          

        An earthquake of magnitude 7.5 on the eastern Bay Area's Hayward fault […], for example, is likely to be far more destructive than the Loma Prieta event.  An “Earthquake Planning Scenario” developed by the California Division of Mines and Geology […] and “An Assessment of the Consequences and Preparations for a Catastrophic California Earthquake” by the Federal Emergency Management Agency […] anticipate the following effects: 

          
           
        • Deaths: 1,500 - 4,500
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        • Injuries: 45,000 - 135,000
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        • Damage: More than $40 billion
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        • One or more hospitals will be destroyed
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        • All four bridges to the East Bay will probably be closed for hours to days
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        • Access to and travel within the East Bay will be difficult and limited to emergency traffic.
        •  
        • Only San Jose International Airport may be available for large aircraft.
        •  
        • The damage in San Francisco is likely to be severe — the Embarcadero area is as close to the Hayward fault as it is to the San Andreas fault.

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    • Social codes crack 

       Sex outside marriage is not only a social taboo in Iran, it's also illegal.  

       Like many provincial towns, Bam is a conservative place, but with families being forced to make their homes in the street, or in camps, the cracks in Bam's strict social codes are being exposed. 

    • Suddenly the private life of Bam isn't private anymore.

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    • Iran , officially Islamic Republic of Iran, republic (2005 est. pop. 68,018,000), 636,290 sq mi (1,648,000 sq km), SW Asia
    • About 10% of the land in Iran is arable; agriculture contributes just over 11% to the GDP and employs a third of the labor force.

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    • but have not solved Iran's structural economic problems, including high unemployment and inflation.
    • Population below poverty line:     40% (2002 est.)

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    • making it Iran's worst recorded disaster ever, rendering some 200,000 people homeless and damaging or destroying some 42,000 housing units.
    • According to UNDP, most buildings in the affected area were constructed by sun-dried brick masonry with extremely poor seismic resistance. Residential units were particularly hard hit given a lack of compliance to construction codes. Prior to the quake, less than three percent of housing units were of steel frame construction.

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    • The Bam earthquake of December 26, 2003 (Mw6.5)  occurred at  01:56:56 (GMT, 05:26:26 local time) around the city of Bam in  the southeast of Iran (Figure-1). The earthquake happened at 5:26 am local  time when most of the inhabitants were sleeping, which could be one of the  causes of the great life loss at the time of the preparation of this report  (29/12/2003). The number of victims was officially declared to be more than  25000 .Also more than 50000 people are declared to be injured and about  100000 people remaine homeless.
    • The monument was constructed mainly from mud-brick and clay. The total area  of this castle is about 6 km2 . There is no information about the  exact date of the construction but according to Persian history it goes back  to more than 2000 years ago and has been repaired many times, and was residential  till 150 years ago.
    • Blame that mortality spread on exponential population growth, increasing poverty, and lax or non-existent building codes. In short: Poor nations run far greater risk of fatalities than rich ones.
    • GeoHazards International, a nonprofit research group aiming to reduce suffering due to natural disasters, measured the lethal potential of seismic disasters facing small and large cities in Asia and the Americas — areas most at risk for seismic calamity. The sample cities spanned both developed and developing countries. Variables measured: building frailty; potential for landslides and fires; and the rescue, firefighting and life-saving medical abilities of local authorities.
    • No more mud 

       It was the prevalence of poorly designed houses built with primitive materials and in disregard of building codes which meant that a tremor of similar strength killed as many as 50,000 in the Iranian city of Bam but only two in quake-prone California the previous week. 

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    • Some 80% of Bam has been destroyed: the city's famous mud-brick constructions collapsed quickly - and crucially left no life-saving air pockets for those crushed as they slept, just suffocating dust. 

       But while a large number of the buildings destroyed in the quake were historical, many were recently constructed, publicly-financed structures, such as the hospital. 

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