基于SBAS-InSAR技术的庆阳北石窟寺区域稳定性监测与分析

区域稳定性监测是石窟寺长期保护的一项重要措施。本研究以庆阳北石窟寺所在区域为对象,基于2019年的15景Sentinel-1A卫星雷达影像,采用小基线集合成孔径雷达干涉测量(SBAS-InSAR)技术对研究区稳定性进行监测,获取了研究区雷达视线向形变速率及时序形变,分析了研究区形变的空间、时间分布规律及其原因。监测结果表明:北石窟寺所赋存的覆钟山山体整体稳定,存在微小形变,不存在潜在滑坡变形特征;研究区主要形变区沿河分布,蒲、茹两河交汇处形变最为明显;研究区时序形变呈现随季节变化的规律性,造成其规律性的原因为随季节变化的土壤侵蚀和董志塬固沟保塬项目的实施。该研究证明了InSAR技术在文物遗址区域稳定性监测的可行性,以及其在具有长期性、可靠性的优势,为石窟寺遗址长期预防性保护提供了新的思路和方法。

SBAS-InSAR-based regional stability monitoring and analysis of the North Grotto Temple in Qingyang

Regional stability monitoring is an important measure for the long-term conservation of grottoes. In this study, the North Grotto Temple in Qingyang was taken as the object. Based on the Sentinel-1A satellite radar images of 15 scenes in 2019, the SBAS-InSAR technology was used to monitor the stability of the studied area. In addition, the radar line of sight deformation rate and time-series deformation in the studied area were obtained. The spatial and temporal distributions of deformation in the studied area and the causes were also analyzed. The monitoring results show that 1) Fuzhong Mountain was stable, as a whole, with small deformation but no characteristics of potential landslide deformation; 2) the main deformation areas in the studied area were distributed along rivers, with the most obvious deformation appearing at the junction of Pu and Ru Rivers; 3) the regularity of time-series deformation in the studied area varied with season, and was due to soil erosion and the implementation of the project for gully consolidation and tableland protection at Dongzhi Tableland. This study has demonstrated the feasibility of the InSAR technology for the regional stability monitoring of cultural heritage sites. Its advantage of long-term reliability provides a new idea and method for the long-term preventive conservation of grotto temple sites.