基于IPTA和SBAS-InSAR结合的广州市南沙区地面沉降监测分析

Land Subsidence Monitoring and Analysis Based on the Combination of IPTA and SBAS-InSAR in Nansha District of Guangzhou

基于2018年12月至2019年12月间的RADARSAT-2数据,本文采用IPTA与SBAS-InSAR技术结合的方法对广州市南沙区进行了地面沉降监测。结果表明,南沙区沉降主要发生在东部南沙镇,最大形变速率达到-140 mm/a。在监测时间范围内,沉降区基本符合线性形变特征。利用同一时间段、同一研究区域的Sentinel-1A数据对RADARSAT-2数据结果进行交叉验证,2种数据结果具有较强的相关性,验证了本文方法的可靠性。最后,简要分析了南沙区地面沉降的原因,内因是软土层自身具有压缩性,外因是城市化建设的影响。

Based on RADARSAT-2 data from December 2018 to December 2019,the method of combining IPTA and SBAS-InSAR technology was used to monitor land subsidence in Nansha District of Guangzhou.The results showed that the subsidence of Nansha District mainly occurred in Nansha Town in the east,and the maximum deformation rate reached-140mm/a.Within the monitoring time range,the settlement area basically conforms to the linear deformation characteristics.The results of RADARSAT-2 data were cross-validated using Sentinel-1A data in the same time period and in the same research area.The two data results have a strong correlation,which verifies the reliability of the method.Finally,It briefly analyzed the reasons for the land subsidence in Nansha District.The internal cause is the compressibility of the soft soil layer,and the external cause is the impact of urbanization.