| Popis: |
Throughout the 20th to the beginning of the 21st century, Nam Dinh coastline, located in the Red river delta, is vulnerable to serious erosion and loss by level sea rise as well as land subsidence. There have been numerous research studies conducted to find out the original causes generating erosion problem. This paper aims to detect and analyze the surface displacements that occurred in this area based on Interferometric Synthetic Aperture Radar (InSAR) and Differential Synthetic Aperture Radar Interferometry (DInSAR) methods. In order to retrieve the most recent ground deformation patterns, Small Baseline Subset (SBAS) technique and specialized software GMTSAR have been exploited in this study. Based on this time-series technique we processed 26 C-band Sentinel-1 SAR images from March 2017 to October 2018 to extract information of land subsidence in whole Nam Dinh coast. The result shows that the displacements calculated in the form of satellite Line of Sight (LOS) are varied from -21 to +2.5 mm/yr. The coastal region where majority of land subsidence occurs along the Red river to Ba Lat mouth, whereas the uplift appears at southern part of the study site, where is the area along the lower Day and Ninh Co rivers. |
