基于SBAS-InSAR技术的豫北平原地面沉降监测

豫北平原是河南省平原地区地面沉降灾害较严重地区之一，快速全面掌握豫北平原地面沉降信息、有效防控地面沉降的持续快速发展对中原城市群建设至关重要。本文借助中高分辨率RADARSAT-2雷达数据，基于SBAS-InSAR技术获取了豫北平原2014-2016年的地面沉降监测数据。监测结果表明：两年内豫北平原地面整体下沉，区内共圈定8个较明显的沉降区，总面积约3 006 km²，各沉降区沉降速率在25.00~114.85 mm/a之间；其中，除安阳县白壁镇-内黄县沉降区和辉县沉降区最大沉降速率分别达到95.36和114.85 mm/a之外，其余6个沉降区最大沉降速率均小于73.58 mm/a。根据沉降区现场实地调查和综合分析发现，豫北平原地面沉降主要是活动断裂、松软岩土、地下水超采、城市建设活动、石油和地热资源开采等共同作用的结果。建议将豫北平原地面沉降的防控重点放在人类活动引起的地下水超采和城市建设引发的松软岩土层超量堆载等方面。

Land Subsidence Monitoring in North Henan Plain Based on SBAS-InSAR Technology

Land subsidence occurs often in the plain of the northern Henan Province.It is very important to rapidly and effectively grasp the information of land subsidence and settlement to the construction of central plains urban agglomeration.Using high and medium resolution data of RADARSAT-2 radar and SBAS-InSAR technology,the land subsidence monitoring records of north Henan Plain from 2014 to 2016 were obtained.The records show that in the two years the whole land subsided in Henan Province,of which eight areas were more seriou swith about 3 006 km² subsidence, and the settlement rate of each area was approximately 25.00-114.85 mm/a. Among them, except the maximum settlement rate of Baibi Town-Neihuang County and Hui County was 95.36 and 114.85 mm/a respectively, the maximum settlement rate of the other six subsidence areas was less than 73.58 mm/a.According to the field investigation and comprehensive analysis of the settlement areas, the land subsidence in north Henan Plain is mainly caused by active faults, soft rock, groundwater overdraft, urban construction activities, and oil and geothermal mining.The authors suggests that the prevention and control of ground subsidence in north Henan Plain should be focused on the excess exploitation of groundwater and overloading of soft rock soil layer caused by city construction.