EARTHQUAKE PROFILE. Figure 1-Seismic hazard map, I.R.Iran

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1 EARTHQUAKE PROFILE The Iranian plateau has long been known as one of the seismically active areas of the world and it frequently suffers destructive and catastrophic earthquakes that cause heavy loss of human life and widespread damage. The I.R.Iran is located in the area of the mountain belt of Alp-Himalayas, which is the last and the youngest mountainous area in the world. The spreading of the Red Sea resulting in the movement of the Saudi Arabian desert towards Iran, the displacement of the Indian Ocean bed in the Oman region towards the northeast, and the movement of other lithosphere plates around Iran have caused circumstances that lead to disastrous earthquakes in Iran every so often, due to the release of energy produced by concentration of stresses in the direction of faults. Over 90% of the country is exposed to the Earthquake hazard (Figure 1). Figure 1-Seismic hazard map, I.R.Iran 1

2 Regarding DesInventar, totally, 3,455 earthquake events (52.7% of all records) were recorded in Iran for the period of , which led to 70,289 deaths, 140,078 injured, 371,033 damaged or destroyed buildings and 1,553,912 affected population. Table 1 indicates the 10 largest earthquakes in Iran for this period, sorted by numbers of killed. Two mega earthquakes happened in term of mortality and destruction, i.e. Rudbar-Manjil (1990) and Bam (2003) earthquake. Table 1- Ten largest earthquakes sorted by numbers of people killed, I.R.Iran, Year Ostan Shahrestan Magnitude Killed Injured 1990 Gilan, Zanjan Rudbar, Manjil, Lushan Building damaged & destroyed Affected population , , , , Kerman Bam ,271 22,739 55, , South Khorasan Ghaenat 7.3 1,700 2,600 12,800 72, Ardebil Ardebil ,600 22,000 38, Kerman Zarand ,621 -* Ghazvin Bouinzahra ,466 41, North Khorasan Bojnurd ,357 84, Kohgiluyeh va Boyerahmad Boyerahmad Lorestan Dorud ,000 52, , Mazandaran Nur ,000 - * No valid data available. 2

3 Percent Figure 2 shows the frequency of earthquake events by magnitude on the Richter scale, recorded by DesInventar Missing >=7.0 Richter scale Figure 2 Earthquake frequency by magnitude (Richter scale), recorded by DesInventar, I.R.Iran, Figure 3 shows that earthquake occurrence was on an increasing trend from 1986 to 2007, mainly earthquakes with magnitude of on Richter scale. Improvement of recording system could be the reason of the upward trend. No clear monthly trend was observed (Figure 4) >= Figure 3- Annual trend of earthquake occurrence by magnitude (on Richter scale), I.R.Iran, >= January February March April May June July August September October November December Figure 4- Monthly trend of earthquake occurrence, I.R.Iran,

4 Percent During , earthquakes were responsible for deaths, 6,670.3 injuries, building damage or destruction, in average, per year. Compared to other natural hazards, during , earthquakes caused 94.9% of recorded mortality, 98.7% of injuries and 73.0% of building damaged or destroyed (Figure 5) Death Injury Building damage Earthquake Other natural hazards Figure 5- Comparison death, injury and building damage or destruction caused by earthquakes and other natural hazards, I.R.Iran,

5 95% CI Death to Injury Ratio (DIR) Mean Death to Injury Ratio (DIR) was 1.2±2.4 with median of 0.1 (range ), given assuming at least one injury for the events with at least one death. Figure 6 indicates mean and related 95% of DIR among different magnitudes of earthquakes. DIR reveals an upward trend with increasing the magnitude, except for magnitude of >=7 on the Richter scale that is related to Rudbar-Manjil earthquake (1990) with death toll of 40,000 and 105,000 injured >=7.0 Magnitude (Richter scale) Figure 6- Earthquake-related Death to Injury Ratio (DIR), I.R.Iran,

6 By increasing the earthquake magnitude, number of death and Death to Buildings damage or destruction Ratio (DBR) increases (Figures 7 and 8). This is true about damage to buildings, except for magnitude of >=7 on the Richter scale that is related to Rudbar-Manjil earthquake (1990) with death toll of 40,000 and 100,000 building damaged or destroyed (Figure 6). It is worthy to mention that number of buildings damaged and destroyed due to Rudbar-manjil earthquakes varies up to two folds between two main sources of information, i.e. from 100,000 according to National Geoscience Database of Iran (NGDIR) to 200,000 according to Ministry of Housing. Figure 7- Death and building damage or destruction by earthquake magnitude, I.R.Iran,

7 Mean Death to Building damage Ratio (DBR) >=7.0 Magnitude (Richter scale) Figure 8- Earthquake-related Death to Building damage or destruction (DBR) by magnitude, I.R.Iran, The highest number of death and building damage happened in the year of 1990 (Rudbar-Manjil earthquake), 1997 (Ardebil earthquake), 2003 (Bam earthquake) and 2006 (Lorestan earthquake). Comparison of DBR in Bam (2003, Mw 6.3) and Lorestan earthquakes (2006, Mw 6.0) shows how important is effective early warning and prompt reaction of the community. While Bam earthquake BDR was 0.48, Lorestan earthquake BDR was calculated as Experts believe that the low mortality of Lorestan earthquake was related to on-time warning issued by Disaster Taskforce once pre-shocks jolted the area and the prompt reaction of people who evacuated their homes. Paying attention to pre-shocks was the valuable lesson that people had learned from Bam earthquake. 7

8 Figure 9- Annual trend of death and Building damaged and destroyed caused by earthquakes, I.R.Iran, Comparing the number of mortality between the periods of and reveals 25% reduction, from 40,196 to 30,093. While buildings damage shows 132% increase in trend, from 111,459 to 259,574 (Figure 10). There is no doubt that the country needs to continue enhancement of mitigation measures in housing and building construction sector, but effective warning in Lorestan earthquake (2006) was a valuable experience that saved thousands of lives. Otherwise we witnessed, at least a flat trend of mortality between two time periods. 8

9 Figure 10- Comparison of earthquake-related death and building damage between and , I.R.Iran Death per 10,000 populations varied among provinces from 0.0 to Gilan (8.35/10,000 inhabitants), Kerman (5.24/10,000 inhabitants) and South Khorasan (1.22/10,000 inhabitants) experiences the highest mortality due to earthquakes in the period of Ghom was the only province with no death. 9

10 The highest numbers of buildings damage or destruction were observed in Gilan (27.4%), Lorestan (18.2%), Kerman (15.8%) and Ghazvin (11.3%). Figure 11- Frequency, death & injury per 10,000 inhabitants and building damaged or destroyed by earthquakes at province level, I.R.Iran, Frequency of earthquake occurrence, number of death, injury and buildings damage or destruction at Shahrestan level is shown in Figure

11 Figure 12- Frequency, death & injury per 10,000 inhabitants and building damaged and destroyed by earthquakes at Shahrestan level, I.R.Iran, Annex Tables 11

12 Table A1- Provincial distribution of death, injury and building damaged and destroyed caused by earthquakes, I.R.Iran, Province No of Death % No of Injury % No of Building damage Ardebil West Azarbayjan East Azarbayjan Bushehr Chaharmahal va Bakhtiyari Esfahan Fars Ghazvin Gilan Golestan Hamedan Hormozgan Ilam Kerman Kermanshah South Khoransan Khorasan-e-Razavi North Khorasan Khuzestan Kohgiluyeh va Boyerahmad Kurdestan Lorestan Markazi Mazandaran Ghom Semnan Sistan va Baluchestan Tehran Yazd Zanjan Total % 12

13 Table A2- Annual distribution of of death, injury and building damaged and destroyed caused by earthquakes, I.R.Iran, Year Death per 10,000 inhabitants Death % Injured % Building % , , , , , , , , , , , , , , , , , , , , , Total , , ,