بررسي توان لرزه زايي گسل‌ها و برآورد تلفات انساني ناشي از زلزله در مناطق شهري مطالعه موردي: (شهر اردبيل)

Study faults can generate earthquakes and estimation of earthquake fatalities in urban areas: A Case Study (Ardabil)

ايران يكي از زلزله‌خيزترين كشورهاي دنيا محسوب مي‌شود و شهرهاي آن در رابطه با اين پديده طبيعي آسيب‌هاي فراوان ديده است. براي كاهش آثار و پيامدهاي ناگوار اين پديده نياز به طراحي برنامه‌هايي براي كاهش ميزان آسيب‌پذيري شهرها در برابر زلزله است، كه مهم‌ترين هدف اين برنامه ها حفظ حيات و زندگي ساكنين مي‌باشد. محدوده مورد مطالعه (شهر اردبيل) توسط گسل‌هاي متعدي احاطه شده و در طول تاريخ زلزله‌هاي متعددي در آن رخ داده است. وجود گسل‌هاي پيراموني و سابقه لرزه‌خيزي آن‌ها مي‌تواند سندي براي وقوع زلزله در زمآن‌هاي آتي باشد كه به عنوان يك عامل تهديد كننده مطرح مي‌باشد. جهت مقابله اصولي با اين پديده و كاستن از ميزان آسيب‌هاي آن نياز به انجام سلسله مطالعاتي در خصوص وضعيت لرزه‌خيزي و توان لرزه زايي گسل‌هاي فعال پيراموني و تخمين ميزان خسارت مالي و جاني به وجود آمده در اثر زلزله‌هاي احتمالي مي‌باشد تا با روشن شدن وضعيت لرزه‌خيزي و ميزان آسيب‌ها، به بررسي عوامل آسيب زا و شناخت نقاط ضعفي كه باعث تشديد آسيب‌ها مي‌شود پرداخت. از اين رو در مقاله فوق براي دست يافتن به اين هدف ضريب لرزه‌خيزي گسل‌هاي مهم پيرامون شهر اردبيل تعيين شد و با مبنا قراردادن نتايج اين مطالعات با استفاده از روش ارايه‌شده توسطCoburn و همكاران تعداد تلفات انساني ناشي از زلزله در شرايط مختلف زماني و امدادرساني تعيين گرديد. بر اساس نتايج به دست آمده معلوم گرديد كه وضعيت وقوع زلزله در شب، بدون هيچ‌گونه امدادرساني، شديدترين تلفات را موجب مي‌گردد. در اين حالت، 74945 از ساكنان يا حدود 55/17% كل جمعيت اردبيل كشته خواهند شد.

Introduction Natural disasters no man is able to directly influence happens and endanger his life. Earthquake is a natural phenomenon that occurs in the case of vulnerable countries, especially developing countries would bring heavy casualties and damage. Iran is one of the worldʹs most earthquake-prone cities in relation to this natural phenomenon has seen a lot of damage. To reduce the harmful effects of these phenomena need to design programs to reduce urban vulnerability to earthquake The main objective of this program is to preserve life and the lives of residents. The study area (Ardabil) as the capital of the province, is home to a large population and has long been a place of business and economic activities. However, the transitive Ardabil surrounded by faults and earthquakes that have occurred throughout history. Surrounding fault and background seismicity evidence for earthquakes in the future they can be The which is considered as a threat. Methodology Principles to deal with this phenomenon and reduce its damage need to conduct a series of studies on the seismicity and seismic potential of active faults surrounding the creation and estimate the extent of damage and the earthquake potential in life there is a place to clarify the situation and the level of seismic damage, the factors that trigger traumatic injuries is to identify weaknesses in the payment finally to reduce or improve weaknesses in the elimination of the damages action. Hence in this paper to achieve the goal of faults on seismic coefficient was determined in Ardabil. Results and Discussion The study was carried out to estimate earthquake risk in the range include: Mapping of a major fault zone to a radius of 100 kilometers, making the device list of earthquakes (earthquakes of the past century have been recorded by the seismograph machines),provide maps of surface centers of earthquakes, fault location and facilities between the surface and the earthquake epicenter, the intensity and magnitude of earthquakes and earthquake prediction features that are likely to occur in the study area by major faults. Based on these studies, the possible accelerated throb of Ardabilʹs fault, is not unexpected, 300cm/s2 is possible intensity of earthquakes that occurred in the city limits can be set Ardabil, 9 Mrykaly scale is correct. Based on the findings of the Astarra fault in creating the highest seismic zone has other faults. In the research process using the results of these studies to estimate the number of casualties caused by the earthquake to the city of Ardabil, the idea (or methods) that stem mortality estimates were presented in 1992 by Coburn et al. Because this method is based on statistical considerations losses from earthquakes around the world, including Iran, Can also be used for Ardabil. Using this method, the number of casualties caused by the earthquake relief in various conditions were determined. Conclusion Based on the results of the study revealed that the earthquake occurred at night, without any relief, it will cause severe losses. . In this case, 74,945 residents, or about%17/55 of the population will die in Ardabil. Mortality in 15 area located in West zone 3 municipalities its large due to population and poor condition of existing structures, it will be very broad. And on the day of occurrence of earthquake relief and emergency relief and professional groups of people will cause the least mortality. In this case, 19,606 people, or about %4/59 of the population will be killed in the city of Ardabil. This could be due to greater awareness of the people in those days could have moreover, a significant part of the day outside the home and are living in the open. In general, the results of studies in the areas of high population density of the city of Ardabil and non-resistant structures associated with low status, the number and rate of fatalities has risen to the same level. While in areas where population density or quality or both of the structures are more favorable has greatly reduced the number of causalities.