MEASURING GROUND SUBSIDENCE IN HO CHI MINH CITY USING DIFFERENTIAL INSAR TECHNIQUES

Abstract

The water table has been constantly lowering and the urbanization has been rapidly developing during the last decades,… due to the strong groundwater extraction has led to the subsidence of some areas in the Ho Chí Minh city. Land deformation at the rate of few centimetres per year can be measured at the heavy ground water pumping stations. Most existing techniques for monitoring ground subsidence base on using methods of precise leveling, and more recently the GPS. These methods are generally expensive and inefficient for monitoring large areas. Besides, sparsely distributed data points are often insufficient to provide information on every localized ground subsidence. Recent advances in the SAR interferometry, especially with the Differential SAR Interferometry is an appropriate satellite remote sensing technique to map subsidence in urban areas at high accuracy and low costs. Results demonstrate the effectiveness of employing the PSInSAR technique for land subsidence monitoring in the Ho Chi Minh city, and this method has enabled a long-term study of vertical land movements using SAR images.