Journal of Spatial Analysis Environmental Hazards

fa تداخل‌سنجی تفاضلی تصاویر راداری به منظور تبیین خطرپذیری شبکه انتقال نفت و گاز از مخاطره زمین-لغزش Risk assessment of gas and oil pipelines due to land sliding hazard based on D-InSAR technique تخصصي Special پژوهشي Research تداخلسنجی راداری تکنیکی کارآمد برای رصد پویایی سطوح است که به کمک آن میتوان ناپایداری سطوح بهخصوص سطوح دامنهای که مخاطرات لغزشی را پیامد دارند، تشخیص داده و مورد پایش قرار داد. تشخیص این مخاطره علاوه بر خطرات شناخته شده و متداول آن در پارهای مواقع میتواند تأسیسات و زیرساختهای مدفون را آسیب رسانیده و خسارات و خطرات فراوانی به همراه داشته باشد. شبکه انتقال نفت از جمله این زیرساختهاست که با عبور از نواحی کوهستانی و مستعد لغزش عموماً در خطر شکستگی و نشت قرار دارند. طبق مطالعات صورت گرفته، پژوهشی به منظور تعیین خطرپذیری خطوط لوله با تکنیک تداخلسنجی راداری در منطقه مورد مطالعه یافت نشد. تحقیق حاضر خطرپذیری شبکه نفت و گاز مارون (مارون-اصفهان) در زاگرس مرکزی از مخاطره زمینلغزش به کمک تکنیک تداخلسنجی رادری را هدف داشته است. بدین منظور دادههای دو سنجنده راداری در باند C و L در مقاطع متفاوت زمانی دریافت و مبتنی بر روش تداخلسنجی تفاضلی میزان تغییرات سطح و جابجاییهای آن محاسبه شد. بر این اساس نرخ حداکثر جابجایی در منطقه حدود 4/7 سانتیمتر بالاآمدگی و 9/3 سانتیمتر فروافتادگی حاصل شد. پس از آن صحت نتایج بدست آمده از مرحله آزمایشگاهی، در پیمایش میدانی با بازدید از 3 زمینلغزش واقع در مجاورت خط لوله و تطبیق مکانی آنها با یافتههای آزمایشگاهی سنجیده شد. سپس پهنهبندی خطر آتی زمینلغزش در 5 کلاس خطر با مدل تجربی ارزش اطلاعاتی تهیه و صحتسنجی شد. مستند به این نقشه، حدود 20 درصد سطح منطقه در کلاس خطر زیاد و بسیار زیاد طبقهبندی شده است. منطبقسازی نقشه کلاسبندی خطر زمینلغزش با مسیر خط لوله نشان داد که 5/28 درصد از طول خط لوله مورد مطالعه در کلاس خطر زیاد و خیلی زیاد، و حدود 52 درصد از آن در کلاس خطر کم و بسیار کم قرار گرفتهاند.   Risk assessment of Maroun gas and oil pipelines due to land sliding hazard based on D-InSAR technique Mohammad Sharifikia, @ Associate professor, Tarbiat Modares University, Department of Remote Sensing- Iran Meral Poorhamzah, postgraduate in Remote Sensing, Tarbiat Modares University Abstract It is importance to note that Iranian oil company have to transfer this valuable enrage from one side to other side of country passing form several ridge and valley prone with several natural hazard. This is because the natural sources of oil and gas generally lied in south west part of Iran locally calling Manathegh Nafte Khize Jonoub (south oil field area). This area is closed to one of most active geological zone of Iran (Zakrose) covering thousands of kilometer from south east to north west. Supplying natural enrages to central port of country need to crossing from this zone which is suffering with several difficulties as well as neutral hazard. Out of neutral hazards can found to excite in this area, the landslide hazard is a main restriction for pipeline crossing over. The present research is dale with radar interferometry techniques applying for risk assessment and mapping over the oil and gas pipelines suffering to landslides hazard in the part of Central Zagros (Maroun-Esfahan). For this purpose, two individual radar dataset in C (ASAR) and L (PALSAR) band with deferent time were collected. Furthermore, the D-InSAR technique was applied for land surface movement and land displacement detection. The outcome map was showed the maximum rate of land displacement in this region is about 7.4 cm uplifted and 3.9 cm subsidence with duration of almost one year. this is due to shape of landslide over the area’s slop. Overlying the landslide map with the pipeline crossing route shown at lies three active landslides over the Maroun-Esfahan gas and oil pipelines. For investigation about this three landslide and damage estimation over the pipeline the field study has been done for accuracy assessment and land movement rat measuring and evaluation. Which, successfully identified and mapped 3 landslides were located across the pipeline and damage it. Furthermore, map surveying by DGPS in RTK method over the one of landslide shown that sliding transfer 20 m with falling 10 m over the length of 45 m of gas pipeline. moreover, the press of landslide made curvatures on straight pip hogging pipe 43 cm. continued this landslide activation and more pressing in close further can make a fracture and pessimistic pipe expulsion. With can a kind of disaster if the event be close to settlements are. The outcome landslide map shown the active landslide points (small area) very well, but the main think need to suffusion information about interred area. For this exigency have to convert points data map to area as prediction hazard. For this proses and to understanding the amplitude of landslide hazard in area the information value model was applied for hazard zonation and mapping. The landslide hazard map resulting from D-InSAR technique as inventory map along with 8 data set maps namely, lito-logy, soil, land cover, lineaments, faults, roads, derange pattern and slop, has been interred to model for zonation and hazard estimation over the area. Furthermore, this map was reclass in 5 individual hazard and risk class from low to high risk. The hazard map analyses and calculation was show about 20 percent of area study was marked as high and very high risk zone. This is mainly because of morphological and lito-logical exclusivity of area resulting by active tectonics. Crooning and overlaying the landslide hazard map with pipeline track has been shown 28.5 percent of line length crossing over the high and very high risk zone, where the 52 percent was prone with low and very low risk zone. This mine that near 1/3 of mention pipeline length suffering from hazardous area which can classified as high risk part of pipeline. Interpreting the hazardous classes on the prediction map is an important concern in landslide prediction models. For this purpose, the prediction-rate curve was generated using validation group of landslide locations to validate the prediction map obtained. This rate curve explains how well the model and factors predict the landslide. Results from the success-rate curve are very promising, since the 3% area predicted as the most hazardous, includes 42.35% of the total area affected by landslides, and this value grows to 90%, when about 25% area of highest susceptibility is considered. The prediction accuracy can be assessed qualitatively by calculation the area under cover. The total area equal to one means perfect prediction accuracy. In this model ratio area was 0.633 that means the prediction accuracy was 63.3%. Keywords: Differential SAR Interferometry, PALSAR, ASAR, Landslide, Oil and Gas Pipeline risk تداخل‌سنجی رادار, خط لوله نفت و گاز, زمین‌لغزش, مارون, خطرپذیری Differential SAR Interferometry, PALSAR, ASAR, Landslide, Oil and Gas Pipeline risk 135 154 http://jsaeh.khu.ac.ir/browse.php?a_code=A-10-810-1&slc_lang=fa&sid=1 mohammad sharifikia محمد شریفی کیا sharifikia@modares.ac.ir 100319475328460010685 100319475328460010685 Yes دانشگاه شهید مدرس Ali mosivand علی موسیوند Ali.mosivand@modars.a.cir 100319475328460010686 100319475328460010686 No دانشگاه شهید مدرس maral poorhamzah مرال پورحمزه pourhamzah@modars.ac.ir 100319475328460010687 100319475328460010687 No دانشگاه شهید مدرس