نوع مقاله : مقاله پژوهشی

نویسندگان

• صدرا کریم زاده ¹
• احمد علی عزیز ²
• خلیل ولیزاده کامران ²
• ماساشی ماتسواکا ³

¹ گروه سنجش از دور و سیستم اطلاعات جغرافیایی، دانشکده برنامه ریزی و علوم محیطی، دانشگاه تبریز

² Department of Remote Sensing and GIS, Faculty of Planning and Environmental Sciences, University of Tabriz, Tabriz, Iran

³ Department of Architecture and Building Engineering. Institute of Science Tokyo, Japan

چکیده

Water conservation and efficient utilization are critical in water-scarce and arid regions such as Iraq. Dams, as vital infrastructure, play a significant role in meeting diverse needs, including water supply, flood control, and maintaining environmental flows. However, improper management of dams can lead to adverse effects on both human populations and ecosystems, disrupt water systems and habitats, and degrade water quality. Addressing these challenges, this study employs the Small Baseline Subset (SBAS) technique, a modern Synthetic Aperture Radar Interferometry (InSAR) method, to analyze displacement rates at Mosul Dam in Iraq. Using 21 ALOS-2 PALSAR-2 L-band radar images, we observed that the central section of the dam is most susceptible to subsidence, while the sides experience less deformation. The average subsidence rate was found to be −2.21 mm/year, with an average cumulative subsidence of −7.18 mm over the study period. The maximum subsidence recorded was −51.70 mm, and the maximum uplift was 30 mm. These findings are based on data collected between November 23, 2014, and March 17, 2024, providing valuable insights into the dam's structural behavior and informing future management strategies.

تازه های تحقیق

This paper investigates ground subsidence in the Al-Mosul Dam from November 23, 2014, to March 17, 2024, using SBAS-InSAR technology, based on 21 ALOS/PALSAR-2 L-band radar images. The following conclusions were drawn: the primary rate of ground subsidence in the dam ranges from −6.77 mm/year to 1.19 mm/year, with an average subsidence rate of −2.21 mm/year. Spatially, subsidence is primarily concentrated in the central part of the dam, corresponding to the old riverbed before the dam’s construction.

The study proved and concluded the existence of variation between uplift and subsidence in the dam body, also for the difference pattern of subsidence velocity during the study period and for different areas above the dam. This fluctuation is attributed to the annual emptying and filling cycles of the reservoir behind the dam. However, the results also indicate a continuous and noticeable overall subsidence trend during the study years. Through field analysis, it was determined that the causes of ground settlement in the Mosul Dam are complex. The dam foundation consists of a variety of soluble rocks, including marls, chalky limestone, gypsum, anhydrite, clays, and heavily fractured limestone. These soluble rocks contribute to the development of karst features. As these rocks dissolve, subsurface cavities form, leading to the collapse of overlying material and surface subsidence. To verify the accuracy of the results, we collaborated with the Mosul Dam Project Management and the team responsible for conducting periodic inspections on-site using traditional measurement devices. They confirmed that the subsidence values recorded in this study are reasonable and closely align with their own measurements. Additionally, they verified that the central area of the dam is the most affected by subsidence, a finding that aligns with the conclusions of this research paper.

کلیدواژه‌ها

• InSAR
• ALOS-2 PALSAR-2
• Subsidence
• SBAS
• Mosul Dam

موضوعات

• سنجش از دور و سیستم اطلاعات جغرافیایی

عنوان مقاله [English]

Surface subsidence over a large structure using SBAS-InSAR with ALOS-2 PALSAR-2 data: The case of Mosul Dam, Iraq

نویسندگان [English]

• sadra Karimzadeh ¹
• Ahmed Ali Azeez ²
• Khalil Valizadeh Kamran ²
• Masashi Matsuoka ³

¹

² Department of Remote Sensing and GIS, Faculty of Planning and Environmental Sciences, University of Tabriz, Tabriz, Iran

³ Department of Architecture and Building Engineering. Institute of Science Tokyo, Japan

چکیده [English]

Water conservation and efficient utilization are critical in water-scarce and arid regions such as Iraq. Dams, as vital infrastructure, play a significant role in meeting diverse needs, including water supply, flood control, and maintaining environmental flows. However, improper management of dams can lead to adverse effects on both human populations and ecosystems, disrupt water systems and habitats, and degrade water quality. Addressing these challenges, this study employs the Small Baseline Subset (SBAS) technique, a modern Synthetic Aperture Radar Interferometry (InSAR) method, to analyze displacement rates at Mosul Dam in Iraq. Using 21 ALOS-2 PALSAR-2 L-band radar images, we observed that the central section of the dam is most susceptible to subsidence, while the sides experience less deformation. The average subsidence rate was found to be −2.21 mm/year, with an average cumulative subsidence of −7.18 mm over the study period. The maximum subsidence recorded was −51.70 mm, and the maximum uplift was 30 mm. These findings are based on data collected between November 23, 2014, and March 17, 2024, providing valuable insights into the dam's structural behavior and informing future management strategies.

کلیدواژه‌ها [English]

• InSAR
• ALOS-2 PALSAR-2
• Subsidence
• SBAS
• Mosul Dam