Detection of Land Deformation Using Differential Interferometric Synthetic Aperture Radar (DInSAR) Technique Over Part of Kaduna State, Nigeria

Abstract

Land deformation poses significant threats to infrastructure, environments and human settlements. However, the need to investigate and assess the rate of land displacement will aid in providing best mitigating approach. This study employed Differential Interferometric Synthetic Aperture Radar (DInSAR) technique to detect land deformation over part of Kaduna state, Nigeria. The observation was carried out in North West Nigeria due to the rapid incidents of earth tremor within the early month of September, in the year 2016 and 2018. Sentinel-1 satellite dataset were used to generate deformation maps, revealing area of uplift and subsidence. InSAR was adopted due to its ability to cover large area and its capability to retrieve deformation data up to millimeter accuracy. Observation was carried out within the interval of 12days from August 30th to October 5th, 2018, covering the whole month of September, 2018. The results show some level of uplift in the region. The displacement varies between -0.011m to + 0.035m (-11mm to +35mm) for interval one, –0.024m to +0.012m (-24mm to 12mm) for interval two, and -0.023m to +0.026m (23mm to 26mm) for interval three. The Kurmin Kwara area had the highest uplift levels with a maximum value of 0.035m. The causes of this deformation may be attributed to excessive earth disturbance either as a result of human factors, such as excessive drilling of borehole and other earth works. The research finding recommend the use of high resolution image data such as COSMOS-SkyMed, ALOS-2; PALSAR-2, along with some other better techniques such as Squee InSAR, PSInSAR for the assessment