مقایسه روش‌های ارزش اطلاعاتی و تحلیل سلسله مراتبی در پهنه‌بندی خطر زمین‌لغزش‌های ناشی از زلزله (مطالعه موردی)

نوع مقاله : Articles

نویسندگان

1 گروه زمین شناسی مهندسی دانشگاه تهران

2 دانشگاه قم

چکیده

امروزه روش های مختلفی برای پهنه بندی خطر زمین لغزش ها وجود دارد. در خصوص زمین لغزش های ناشی از زلزله اما تحقیقات محدودتری انجام شده است. بررسی و تحلیل مشخصات زمین‌لغزش‌های ناشی از زلزله و نحوه توزیع آن‌ها در شناخت مناطق مستعد زمین‌لغزش در زلزله‌های آینده اهمیت بسزایی دارد. هدف از این مطالعه شناسایی عوامل مؤثر و پهنه‌بندی زمین‌لغزش‌های ناشی از زلزله به روش‌های ارزش اطلاعاتی و تحلیل سلسله مراتبی در محدوده ای در نزدیکی رومرکز زلزله منجیل به مساحت 30/309 کیلومترمی باشد. در این مطالعه با استفاده از دو مدل رگرسیون دومتغیره (ارزش اطاعاتی) و تحلیل سلسله مراتبی پهنه بندی خطر زمین لغزش های ناشی از زلزله انجام شده و کارایی این دو روش مورد بررسی و مقایسه قرار گرفته است. به این منظور، ابتدا با توجه به موقعیت زمین‌لغزش‌های به وقوع پیوسته، بررسی‌های تطبیقی و نتایج سایر محققین، 7 عامل شامل شدت آریاس، زاویه اصطکاک داخلی، شیب، چسبندگی، جهت شیب، ارتفاع و انحنای دامنه به عنوان مهمترین عوامل وقوع زمین لغزش های ناشی از زلزله منجیل شناسایی شده و لایه‌های رستری عوامل مذکور در محیط سامانه اطلاعات جغرافیایی (GIS) تهیه گردید. نقشه فهرست زمین‌لغزش‌ها نیز با استفاده از عکس‌های هوایی و مشاهدات میدانی تهیه و درکنار سایر اطلاعات قرار گرفت. تمامی اطلاعات و داده‌های تهیه شده جهت آنالیز اولیه وارد محیط GIS شد و نقشه های پهنه بندی خطز زمین لغزش های ناشی از زلزله با در نظرگرفتن روش های مذکور انجام شد. سپس کارایی دو روش مورد بررسی با استفاده از دو شاخص جمع کیفیت‌ها (QS) و دقت روش (P) مورد بررسی قرار گرفت. نتایج نشان می‌دهد که مدل رگرسیون دومتغیره (روش ارزش اطلاعاتی) نسبت به روش تحلیل سلسله مراتبی روش مناسب‌تری بوده و نتایج آن با واقعیت تطابق بیشتری دارد.

کلیدواژه‌ها


عنوان مقاله [English]

Comparison of Information Value Method and Analytical Hierarchy Process in the Earthquake-Induced Landslides Hazard Zonation (A Case Study)

نویسندگان [English]

  • Mohammad Rajabi 1
  • Hossein Khosravi 2
1 School of Geology, Engineering Geology Department, University of Tehran, Tehran, Iran
2 Geotechnical Engineering Department, University of Qom, Qom, Iran
چکیده [English]

Although many studies have been done on the landslide hazard zonation, landslide caused by the earthquake has received less attention. Analysis of features of landslides caused by the earthquake and their distribution is very important in recognizing landslide-prone areas for future earthquakes. The purpose of this study is to identify the effective factors and zonation of landslides caused by the earthquake through information value and Analytical Hierarchy Process (AHP) methods in the area near the epicenter of the Manjil earthquake with an area of 309.30 km. In this study, landslide hazard zonation caused by earthquake was performed by using bivariate regression (information value) and AHP, and the efficiency of these two methods were studied and compared. Hence, according to the landslides location, comparative studies and the results of other researchers, seven factors including Arias intensity, internal friction, cohesion, slope angle, aspect, direction, elevation and terrain rough, have been identified as the most important factors in the landslides caused by Manjil earthquake. Then, these factors were prepared in a Geographical Information System (GIS). All information and data for the initial analysis were imported into GIS, and zonation maps of the landslide caused by the earthquake were prepared with regard to the above-mentioned methods. For this purpose, in the information value method, the inventory map has been initially integrated with the maps of effective factors in the landslides occurrence. After calculating the weight of each subclass of factors and finally adding the results of the previous stage in the information layer table in the Arc GIS, landslide hazard zonation map was obtained by this method. Through using the expert opinions and the tables used in the AHP method, the effective criteria and sub-criteria in the occurrence of landslide caused by earthquakes in the study area were compared. Afterward, the results of these comparisons were placed in Expert Choice software, and the relative weights of each criteria and sub-criteria was obtained. Then, the obtained final weights were added to the effective factors information layer table. Finally, hazard zonation map of landslide caused by earthquake in the study area was obtained by this method. According to the results of AHP method, Arias intensity and terrain rough factors had highest and lowest impact on the landslide occurrence. The greatest impact for sub-criteria 10–11.54 is related to the Arias intensity, and minimum impact is related to the smooth sub-criteria of terrain rough factor. Further, according to the zonation maps obtained by these two methods, the models obtained from AHP and the information methods, high risk and very high risk zones have respectively constituted 73 and 52 percent of the region. After reviewing the efficiency of procedures employed in this study by using two quality sum (QS) and precision (P) indicators, the results showed that bivariate regression model is more appropriate than AHP method and its results are more consistent with reality.

کلیدواژه‌ها [English]

  • Manjil Earthquakes
  • Landslides Caused by Earthquake
  • hierarchical analysis
  • Value of Information
  1. - Mahdavifar, M. R. (2006) Risk Management Assessment System Analysis and Design landslides caused by the earthquake in the country. PhD thesis Institute of Seismology and Earthquake Engineering (in Persian).
  2. - Rajabi, A. M. (2010) Investigation of the possible risk of landslides caused by the earthquake in Iran. "Ph.D thesis Geological Engineering, Faculty of Science, Tarbiat Modarres University (in Persian).
  3. - Bagheri, V. (2012) Zoning landslides caused by earthquakes (earthquakes Ardebil Case Study). "Master's thesis, University of Tehran Award (in Persian)
  4. - Komakpanah, A. and Hafezimoghadas, N. (1993) Landslide zone in Iran, Volume 6: identify and to map important landslide triggered by the earthquake of May 1369 Manjil. "Institute of Seismology and Earthquake Engineering (in Persian).
  5. - Nogolsadat, M. (1996) Drift Master Plan of Gilan province. "Client: earthquakes and landslides layer of the Earth Sub-Committee for Planning and Architecture Department of Housing and Urban Development Department (in Persian).
  6. - Mahdavifar, M.R., Solaymani, S. and Jafari, M.K., 2002. Landslides triggered by the Avaj, Iran earthquake of June 22. Engineering Geology, 86, 166–182.
  7. - Memarian, P. and Mahdavifar, M. (2012) Distribution and Characteristics of Landslides Induced by the Varzeghan Ahar Earthquake Doublet (Mw= 6.4 and Mw= 6.3) in 2012 in Azerbaijan E Sharghi, Northwest of Iran. IPL Symposium (pp. 35).
  8. - Memarian, P et al. (2015) Earthquake-induced rock fall hazard zonation of Varzegha-Ahar region in northwest Iran: a comparison of quantitative and qualitative approaches.
  9. - Jaferi, M et al. (2000) "Studies related to the earthquake in Alborz landslides." Institute of Earthquake Engineering and Seismology (in Persian).
  10. - Ayalew, L. and Yamagishi, H., 2005. The application of GIS- based logistic regression for landslide susceptibility mapping in the Kakuda- Yahiko Mountains, Central Japan. Geomorphology, 65, 15-31.
  11. - Godsi Poor, H. (2009). "Analytic Hierarchy Process." Seventh Edition, Tehran's Amirkabir University Press (in Persian).
  12. - Saaty, T.L., (1986), Axiomatic foundation of analytical hierarchy process, Journal of Management science, Vol. 31, No. 7, Pp. 841- 855.
  13. - Pradhan B et al., (2006). Estimation of stress and its use in evaluation of landslide prone regions using remote sensing data. Advances in Space Research 37: 698– 709.
  14. - Gee, M.D., 1992. Classification of River Basin. Central Italy, Environmental management, 25, 247-263.
  15. - Jade, S. and Sarkar, S., 1993. Statistical Models for Slope Instability Classifications Engineering Geology. 36, 91-98.