D-InSAR技术在煤矿区沉陷监测中的研究

文章介绍了近年来D-InSAR技术在煤矿区沉陷监测的应用和发展,探讨了该技术用于监测煤矿区沉陷的可行性、与传统的变形监测技术对比所具有的优势,并指出了目前该技术在煤矿区沉陷监测中存在的问题及解决方法。     

干涉测量技术在矿山塌陷和地面沉降监测中的应用

差分干涉测量（D-InSAR）技术，是合成孔径雷达（SAR）卫星应用的一个拓展。雷达图像的差分干涉图可用于监测cm级或更微小的地面形变，具有全天候、大面积监测地面沉降和矿山塌陷的优势。本文以武安矿山塌陷和沧州市地面沉降监测为例，介绍了这一新技术在灾害监测领域中的实际应用。     

基于SBAS-InSAR技术的煤矿开采沉陷监测与分析

地下煤炭资源大量开采导致的地表形变,引发严重的安全和环境隐患,雷达干涉测量技术是高精度、大范围地表形变监测的重要手段之一。以辽宁省沈阳市沈北新区蒲河煤矿为例,采用SBAS-InSAR技术探测2018—2019年矿区地表形变结果,获取了采煤引起地表形变的时空分布特征,结合采场所在区域的地质条件和变形诱发因素,利用数值模拟技术对观测形变结果进行模拟分析,进而讨论了蒲河煤矿地面沉降在时间和空间上的变形规律和机制。InSAR形变监测结果显示,开采区域内存在两处沉降漏斗,且数值模拟结果与InSAR形变观测值分布规律一致,反演结果接近实际情况,可为相关部门制定地面沉降防治措施提供科学依据。     

合成孔径雷达差分干涉形变监测的质量评定分析

通过对D-InSAR数据处理过程中的不同误差进行分析,尤其是通过对差分干涉图和相位解缠的质量指标进行了详细分析和比较,研究了D-InSAR监测方案的质量评定与方案选取问题。并以西安地区1992-1993年间不同航迹,不同ERS干涉对的三个地面沉降监测方案为例进行了试验分析,结果显示采用干涉图和相位解缠的质量评定指标可以很好的进行监测方案的优选。     

基于D-InSAR技术的淮南矿区地面沉陷监测

针对常规的通过大地水准测量、GPS测量监测矿区地面沉陷的技术存在监测周期长、成本高、无法全面监测等缺陷,提出了一种基于D-InSAR技术的矿区地面沉陷监测方法。以淮南矿区为试验区,采用两轨法D-InSAR技术,利用该地区2个时相的ALOS PALSAR数据获取了淮南矿区试验时间段内的地面形变图,分析了淮南矿区各矿的地面沉陷信息。结果表明,煤矿开采区存在5~25 cm不同程度的沉陷,与实际情况相符,因此,基于D-InSAR技术的监测方法可以作为一种获取矿区大范围的地表沉陷信息的有效方法。     

基于Sentinel-1A数据反演九寨沟地震地表形变场

针对四川省九寨沟2017年8月8日发生的7.0级地震引起的地表形变,使用欧空局2014年发射的Sentinel-1A卫星C波段雷达影像数据,采用两轨雷达差分干涉技术(D-InSAR)处理得到了研究区范围内同震形变场。干涉结果显示,此次地震造成了明显的地表形变,景区内最大抬升达到了12.6cm,最大沉降达9.8cm。研究结果表明:Sentinel-1A卫星的C波段雷达数据非常适用于对植被覆盖葱郁、地形复杂的区域进行D-InSAR形变监测。D-InSAR技术获取的地表形变信息可用于分析讨论地震受灾范围和地震机理。进一步明确了D-InSAR技术在大范围地表形变探测和地学研究范畴的重要地位。     

基于PS-InSAR的天津地区沉降监测及分析

城市地面沉降监测是保障城市安全建设和健康发展的重要手段之一,而传统的沉降监测方法无法大尺度反映地面形变信息。针对近几年天津地区出现大面积沉降现象,利用Sentinel-1A数据基于永久散射体干涉测量技术开展城区大范围沉降监测研究并分析了地面沉降原因。结果表明：近年来天津地区多处出现地面沉降,严重沉降区集中天津的武清区、北辰区以及郊区乡镇结合区域的王庆坨镇、胜芳镇、左各庄镇、静海镇以及大寺镇,其最大沉降漏斗位于王庆坨镇,沉降速率为-63.2 mm/a。经分析发现天津地面沉降与地下水过度开采、大型工业区的迁移和建设以及活动断裂带地质活动有关。     

基于PS-InSAR的天津地区沉降监测及分析

城市地面沉降监测是保障城市安全建设和健康发展的重要手段之一，而传统的沉降监测方法无法大尺度反映地面形变信息。针对近几年天津地区出现大面积沉降现象，利用Sentinel-1A数据基于永久散射体干涉测量技术开展城区大范围沉降监测研究并分析了地面沉降原因。结果表明：近年来天津地区多处出现地面沉降，严重沉降区集中天津的武清区、北辰区以及郊区乡镇结合区域的王庆坨镇、胜芳镇、左各庄镇、静海镇以及大寺镇,其最大沉降漏斗位于王庆坨镇，沉降速率为-63.2 mm/a。经分析发现天津地面沉降与地下水过度开采、大型工业区的迁移和建设以及活动断裂带地质活动有关。     

基于SBAS-InSAR技术的围填海区域地面沉降监测

以围填海活动为代表的沿海快速城市化过程,是引起地面沉降的重要影响因素之一。研究聚焦沿海围填海活动热点区域广州市南沙区,使用2015年6月~2018年4月共34景Sentinel-1数据,应用SBAS-InSAR技术,揭示了南沙区在研究时段内地面沉降的时空变化格局及演变特征。结果表明：①南沙区整体呈现持续沉降的趋势,沉降速率分化严重,平均沉降速率达到3.2 mm/a,圈层分析法显示中心圈层平均沉降速率为2.6 mm/a,最外层平均沉降速率为26.8 mm/a;②该区地面沉降在空间上呈现出异质性,主要分布在东部和南部,其中南部万顷沙、龙穴岛地面沉降最为严重,最大年沉降速率达到72.2 mm/a,在2015年6月~9月还出现地面沉降回弹现象,可能是台风天气带来季节性强降水变化影响。③基于不同极化方式的Sentinel-1数据进行交叉验证,VV极化、VH极化监测结果平均值分别为2.09 mm和1.01 mm,均方根误差分别为1.12 mm和2.65 mm。结果表明：SBAS-InSAR技术在提取围填海区域的地面沉降信息方面是有效可靠的,能更好地为监测沿海地区的地面沉降情况提供科学依据。     

基于PSI技术的芜湖市地面沉降时空特征分析

城市的沉降监测有利于了解区域实时高程,可为地质灾害与防护部门提供数据依据,避免因高程损失而带来的地质灾害。基于2016年1月至2017年12月共22景Sentinel-1A干涉宽幅模式影像数据,利用永久散射体合成孔径雷达干涉测量技术以及合成孔径雷达差分干涉测量技术进行芜湖市地表形变监测,并分析研究区地面沉降的时空分布特征。空间上,阐述芜湖市地面沉降的整体格局,再以道路为专题,分析了道路的沉降分布格局。时间上,以时间为基线,逐月分析地面沉降部分在年内的具体变化。结果表明：空间上,芜湖市地面沉降主要集中在长江以东的范围,呈现出由西向东逐渐增加的趋势,长江以西呈现零星漏斗式沉降分布,其中,沉降累积量也与道路的密度与建设相关,道路汇集区与修建区域的沉降累积量较大;时间上,研究区整体沉降量各月变化较均匀,其中,沉降量变化范围在6月最大,10月与11月最小。     

Combining differential SAR interferometry and the probability integral method for three-dimensional deformation monitoring of mining areas

With the exploitation of coal resources, ground surface subsidence continues to occur in mining areas, destroying the ecological environment and significantly affecting the daily productivity and life of humans. The differential synthetic aperture radar interferometry (D-InSAR) technique is widely used to monitor ground surface deformation because of its unique advantages such as high accuracy and wide coverage. However, conventional D-InSAR technology provides only one-dimensional (1D) displacement monitoring along the radar line of sight (LOS). This article proposes a method based on an analysis of the mining subsidence law for true three-dimensional (3D) displacement monitoring by combining D-InSAR and a subsidence prediction model based on the probability integral method. In this approach, 1D displacement, obtained using D-InSAR, is then combined with the prediction model to obtain the 3D displacement of ground surface target points. Here, 3D displacement curves were obtained for the Fengfeng mining area (China) using RadarSat-2 images obtained on 9 January and 2 February 2011. True ground surface displacement was measured simultaneously by levelling when the 152under31 s working face was being exploited in Jiulong mine. Vertical displacement and inclined deformation calculated using the proposed method were compared with levelling survey data and the results showed average differences of 3.2 mm and 0.1 mm m^?1, respectively; the calculated maximum displacement in the east–west and south–north directions were 106 and 73 mm, respectively. The spatial distribution of the displacements was in accordance with the mining subsidence law. Thus, the new method can retrieve highly accurate 3D displacements caused by mining subsidence.     

基于国产小卫星遥感数据的矿区土地覆盖与景观格局变化研究

采用北京一号小卫星和环境与灾害监测预报小卫星遥感数据,对徐州西矿区2008年～2009年土地利用/覆盖及景观格局变化进行分析。通过对4种分类方法的比较,选择精度最高的决策树分类图进行分析。试验表明:采矿活动导致徐州西矿区植被面积下降明显,大部分转为建筑用地;同时,矿区土地复垦使塌陷积水面积减少;区域景观破碎化程度有所下降,斑块的形状趋于规则化,景观多样性减小。评价变化检测精度,结果表明:国产小卫星遥感数据能有效地应用于矿区土地利用/覆盖及景观格局变化监测。     

Dynamic monitoring of land subsidence in mining area from multi-source remote-sensing data – a case study at Yanzhou,China

Energy consumption in China is currently based on coal, but the exploitation of coal resources is accompanied by serious threats to the environment. In order to balance mine exploitation, land resource protection and land reclamation, there is an opportunity for monitoring land subsidence in mining area. This article examines a case study of Yanzhou mining area (YZMA) and proposes a new method for dynamic monitoring of land subsidence, which is a hybrid approach using a combination of multi-scale edge detection, relational model establishment and digital elevation model (DEM) difference analysis. A wavelet transform is used to extract the edges of water and marsh, which are buffered with the model to achieve the acquisition of the subsidence edge. DEM difference analysis is finally used to modify the results. The results indicate that this hybrid method improves subsidence monitoring performance by ±0.02 km² of the area accuracy. This method can be viewed as an effective approach to monitor a wide range of land subsidence in plain mining areas of China.     

采煤塌陷区地形渲染研究

随着煤炭的大量开采,塌陷区逐渐增多,严重地破坏了矿区生态结构,影响了矿区及周边地区人们的生活。因此良好的塌陷区漫游系统成为了治理这些危害的关键。三维地形是可视化系统及虚拟仿真的基本组成部分,也是此次项目至关重要的一部分。针对当前三维地形及其渲染技术的研究现状,该文结合常用图形接口OPENGL,在VC＋＋6.0平台下,运用GIS技术和采煤塌陷区地形数据,对LOD技术和ROAM算法进行研究,更好地实现塌陷区漫游效果。     

Data fusion for investigating land subsidence and coal fire hazards in a coal mining area

Coal mining areas all over the world are often threatened by serious environmental hazards such as the occurrence of coal fires, land subsidence, etc. Coal fires burn away the natural non-renewable coal resources, locally raise the temperature of the area, emit polluting gases such as oxides of carbon, sulphur and nitrogen, and when present underground are even the cause of land subsidence. Mining-induced subsidences, on the other hand, cause horizontal and vertical movements in the land surface, and open cracks and fissures that serve as inlets for oxygen, which in turn aggravate the problem of coal fires. These inter-related phenomena often render the mining areas unfit for human inhabitation and the commercial exploitation of coal nearly impossible in some parts. In this study, satellite data acquired in three regions of the electromagnetic spectrum, namely optical, thermal and microwave, along with field data, are used to identify the areas affected by coal fires and land subsidence in a coalfield in north-west China. Data fusion techniques are used for an integrated analysis of this complex problem.     

Analysis of ground subsidence at a coal-mining area in Huainan using time-series InSAR

In Huainan City, Anhui Province, China, ground subsidence persistently occurs due to underground coal mining, which has caused several environmental issues. A modified time-series Interfermetric synthetic aperture radar (InSAR) technique is applied to obtain ground movement in Huainan over a period of approximately two years using 20 ascending Radarsat-2 images. In particular, distributed scatterers (DSs) are efficiently identified using classification information and statistical characteristics. Classified information is used to identify the specific DS classes and statistical characteristics are used to refine the DS candidates. To control error propagation and improve computational efficiency, the deformation rate and digital elevation model (DEM) error of persistent scatterers (PSs) are first retrieved using conventional persistent scatterer intermemetry (PSI). Then, a region-growing-based strategy is applied to extract the deformation rate of DSs. Land subsidence is detected in coal-mining areas of central Dingji, Guqiao, Zhangjiaji, Xinji I, and Xinji II, which suggests that the subsidence is primarily caused by underground mining. The fastest subsidence occurring in non-urban areas is particularly vulnerable to subsidence and collapsed lakes. It is also found that the collapsed lakes have expanded during the observation period, with an expanded mining area of 0.842 km² near Guqiao. A linear relationship between the observed subsidence and expansion of collapsed lakes was found, which indicates that the expansion of collapsed lakes hass resulted from subsidence due to underground coal mining.     

开采厚度对沿空掘巷围岩稳定性的影响分析

目前大多煤矿根据平均开采厚度来确定煤柱宽度,进而指导沿空掘巷,然而煤层在形成过程中受各种因素影响,存在同一煤层厚度变化较大的情况。针对综放工作面煤层开采厚度变化大,导致沿空掘巷围岩变形差异大及破坏机理复杂等问题,采用FLAC 3D软件建立巷道模型,分析平均开采厚度下的围岩变形和破坏规律,并确定合理的煤柱宽度:平均开采厚度为18 m时,在实体煤帮侧,煤体内支承压力峰值与煤柱宽度呈正相关,且煤柱宽度大于8 m后,支承压力增长幅度变缓,因此合理的煤柱宽度应为8 m。在煤柱宽度确定的情况下,研究开采厚度对沿空掘巷围岩稳定性的影响,结果表明:煤柱宽度为8 m时,随着开采厚度的增加,顶板剪破坏面积增大,覆岩变形范围与顶板下沉量增大,但两帮剪破坏面积和两帮移近量减小;当煤层开采厚度小于18 m时,煤柱内支承压力峰值与煤层开采厚度呈负相关;当煤层开采厚度大于18 m时,煤柱内支承压力峰值与煤层开采厚度呈正相关,但增长幅度较小。根据数值模拟结果得出结论:开采厚度的增大对沿空巷道两帮的围岩控制有一定益处,但对顶板维护不利,对开采厚度较大的部位应及时补加锚杆进行强化支护。现场实际应用验证了本文研究的可靠性和有效性。