基于PSInSAR技术的唐山南部沿海地区地面沉降研究

LAND SUBSIDENCE OF COASTAL AREA IN SOUTHERN TANGSHAN USING PSInSAR TECHNIQUE

唐山南部沿海地区是唐山市地面沉降灾害较严重的地区,地面沉降的快速发展对唐山世界级重化工业基地的功能发挥构成严重威胁,全面了解唐山南部沿海地区地面沉降的分布演化态势及其发育主导因素至关重要。基于中高分辨率雷达数据,采用PSInSAR技术获取唐山南部沿海地区地面沉降场的分布及演化信息,可以发现这一地区的区域地面沉降漏斗与地下水位下降漏斗具有良好的对应关系,且沉降区范围沿区内基底断裂带一侧展布。但在曹妃甸工业区,地面沉降特征与过量开采地下水引起的地面沉降特征有所不同,地面沉降区呈点状、斑状分布,沉降区范围较小,沉降中心的沉降梯度大。据调查,特殊的地质环境是该区地面沉降发育的基础条件,地下水超采、大规模工程扰动是诱发和加剧地面沉降的外在动力。

The rapid development of ground subsidence in the southern Tangshan area is serious and has threated its world-class chemical industry base. Therefore, this paper examines the distribution and evolution of ground subsidence in the coastal area of the Southern Tangshan area, as well as the dominant factors of different subsidence regions. Based on the medium and high resolution radar data, the ground subsidence result in the coastal area of the southern Tangshan is obtained using PSInSAR technique. The results show that the ground subsidence funnel has a well correspondence with the groundwater funnel area. The ground subsidence is distributed along one side of a basement fault. The ground subsidence distribution of the Caofeidian Industrial Area is spotty or patchy, and its area range is small but the settlement gradient very large, which is extremely different from the ground subsidence caused by excessive exploitation groundwater. According to this survey, the geological characteristics are the basic condition of ground subsidence development, while over-exploitation groundwater and large-scale engineering disturbance are external power in Southern Tangshan area.