El Kamali Muhagir, Saibi Hakim, Abuelgasim Abdelgadir
National Water and Energy Center, Department of Geography & Urban Sustainability, United Arab Emirates University, Al-Ain, Abu Dhabi, 15551, United Arab Emirates.
Department of Geosciences, United Arab Emirates University, Al-Ain, Abu Dhabi, 15551, United Arab Emirates.
Environ Res. 2022 Sep;212(Pt D):113505. doi: 10.1016/j.envres.2022.113505. Epub 2022 May 27.
The integration of geophysical and satellite-based monitoring techniques can yield new insights in land surface deformation (LSD) studies. In this study, we integrated the microgravity monitoring geophysical technique with Interferometry Synthetic Aperture Radar (InSAR) to reveal the possible sources of LSD changes. A microgravity survey was conducted over Al-Ain city for 1 year at one-month intervals, with time-lapse microgravity changes calculated based on the results. Over the same area of interest and time interval, InSAR analysis was performed using Sentinel-1 (C-band) data. The time-lapse microgravity changes for the whole studied period ranged from -36 to 365 μGal. The InSAR processing showed periodic land surface deformation over the area of interest varying with the season of the year. The InSAR technique detected land surface subsidence at the northeast and western parts of the study area (-7 mm/year and -8 mm/year, respectively) and land surface uplift in the central and southern parts of the study area (2 mm/year). The recorded subsidence may relate to water extraction in these areas. The integration of the two techniques showed a negative correlation, with coefficients of -0.43 and -0.39 for land surface subsidence and uplift, respectively. Furthermore, groundwater level drawdown zones were identified in the west and center of the study area. Overall, LSD is mainly stimulated by water volume exploitation in the Al-Ain region.
地球物理监测技术与基于卫星的监测技术相结合，可为地表形变（LSD）研究带来新的见解。在本研究中，我们将微重力监测地球物理技术与合成孔径雷达干涉测量（InSAR）相结合，以揭示LSD变化的可能来源。在艾因市进行了为期1年的微重力测量，测量间隔为1个月，并根据测量结果计算了随时间变化的微重力变化。在相同的感兴趣区域和时间间隔内，使用哨兵-1（C波段）数据进行了InSAR分析。整个研究期间随时间变化的微重力变化范围为-36至365微伽。InSAR处理结果显示，感兴趣区域的地表形变具有周期性，且随一年中的季节而变化。InSAR技术检测到研究区域东北部和西部存在地表沉降（分别为-7毫米/年和-8毫米/年），而研究区域中部和南部存在地表隆起（2毫米/年）。记录到的沉降可能与这些地区的地下水抽取有关。两种技术的结合显示出负相关，地表沉降和隆起的相关系数分别为-0.43和-0.39。此外，在研究区域的西部和中部确定了地下水位下降区。总体而言，LSD主要是由艾因地区的水量开采引起的。
