Temporal and Spatial Analysis of Deformation Monitoring of the Ming Great Wall in Shanxi Province through InSAR

Abstract

The Great Wall of China constitutes a significant cultural treasure of the Chinese nation and a valuable piece of heritage of world civilization. Owing to both natural and anthropogenic factors, the Great Wall is undergoing gradual deformation, thereby posing considerable challenges to the overall preservation of the associated sites. This study aims to investigate techniques for monitoring deformation at large-scale linear heritage sites, leveraging the Great Wall as a representative example, and to offer valuable insights for monitoring surface deformations at extensive cultural heritage sites worldwide. Employing SBAS-InSAR technology, this research analyzes and monitors the deformation of the Great Wall. A series of Sentinel-1A images captured between March 2017 and January 2022, consisting of 161 scenes, were subjected to SBAS-InSAR processing to derive the deformation rate field along the wall. To ensure the reliability of the findings, a representative mountainous segment, spanning approximately 896.53 km within the scenic corridor of the Great Wall, was selected for analysis. The outcomes indicate that 75.8% of the scenic corridor in Shanxi Province, representing the Ming Great Wall, exhibits relative stability with deformation rates ranging from −10 to 10 mm/year. Conversely, 24.2% of the scenic corridor demonstrates significant deformation, with a maximum subsidence rate of 33.1 mm/year and a maximum subsidence of 148.6 mm. Therefore, this research highlights the potential application of SBAS-InSAR technology in the monitoring and assessment of surface deformation at massive linear cultural heritage sites and offers a reference point for similar monitoring efforts on a global scale.