地震工程学报
地震工程學報
지진공정학보
China Earthquake Engineering Journal
2015年
1期
196-201
,共6页
PS-InSAR%泉州地区%永久散射体%断裂带%地壳形变
PS-InSAR%泉州地區%永久散射體%斷裂帶%地殼形變
PS-InSAR%천주지구%영구산사체%단렬대%지각형변
PS-InSAR%Quanzhou area%PS upermanet scatterers%fault zone%crustal deformation
PS-InSAR 技术能够有效降低常规差分干涉雷达受时间失相干、空间失相干和大气效应的影响,在常规 D-InSAR 不能形成干涉条纹的情况下,可利用时间序列的雷达影像和相位稳定的永久散射体目标点获取离散的 PS 像素点形变速率。以福建省泉州地区的断裂带为研究对象,对1996-1999年的22景 ERS SAR 数据进行 PS-InSAR 处理,得出研究区主要断裂的视线向位移速率为3~5 mm/a,表明该区断裂仍有一定的活动性,具有潜在的地震危险。
PS-InSAR 技術能夠有效降低常規差分榦涉雷達受時間失相榦、空間失相榦和大氣效應的影響,在常規 D-InSAR 不能形成榦涉條紋的情況下,可利用時間序列的雷達影像和相位穩定的永久散射體目標點穫取離散的 PS 像素點形變速率。以福建省泉州地區的斷裂帶為研究對象,對1996-1999年的22景 ERS SAR 數據進行 PS-InSAR 處理,得齣研究區主要斷裂的視線嚮位移速率為3~5 mm/a,錶明該區斷裂仍有一定的活動性,具有潛在的地震危險。
PS-InSAR 기술능구유효강저상규차분간섭뢰체수시간실상간、공간실상간화대기효응적영향,재상규 D-InSAR 불능형성간섭조문적정황하,가이용시간서렬적뢰체영상화상위은정적영구산사체목표점획취리산적 PS 상소점형변속솔。이복건성천주지구적단렬대위연구대상,대1996-1999년적22경 ERS SAR 수거진행 PS-InSAR 처리,득출연구구주요단렬적시선향위이속솔위3~5 mm/a,표명해구단렬잉유일정적활동성,구유잠재적지진위험。
The interferometric SAR (Synthetic Aperture Radar)technique has the capability to measure ground deformation in a wide range of applications.It is possible to exploit (Differential-)SAR interferometry to measure small terrain displacements,but single measurements can be considered reliable only in cases of larger displacements,and several types of incoherent temporal change reduce the accuracy of the interferometric phase.The exploitation of several measures (i. e.,interferometric stacking and analysis of SAR phase time series)is of great interest with regard to the improvement of single measurements.The exploitation of a series of N SAR images (inter-ferometric stacking)allows the identification of areas (pixels)that show a coherent and consist-ent signal (displacement)over time.The persistent scatterer (PS)-InSAR technique,which is more applicable to point targets and man-made features than InSAR,can effectively reduce the losses of temporal and spatial coherence,and reduce the influence of atmospheric effects.In cases where interference fringes of conventional D-InSAR cannot be formed,radar image time series and the phase stability of permanent point targets can be used to obtain deformation rates of discrete PS pixels.The Stanford method for persistent scatterers (StaMPS)software package that imple-ments an InSAR persistent scatterer (PS)method is used in the study.There are two preprocess-ing steps necessary before beginning the PS/MTI processing method:focusing of the raw data and forming interferograms from single-look complex images.ROI PAC was used for the focusing and Doris for the interferogram formation.The fault zones located in Quanzhou in Fujian Province are the research object,and 22 ERS SAR datasets from 1 996 to 1 999 were used for processing by the PS-InSAR method.After the steps of SLC image generation,interferogram formation,phase noise estimation,PS selection,PS weeding,phase correction,and phase unwrapping,the time series of each pixel was processed separately and a set of height residuals and average displacement rates was extensively tested;the pair “flattening at best”the measured phases was selected as the solu-tion.We obtained the crustal deformation that corresponded to the maximization of the temporal coherence of the pixel time series for a linear displacement of the active fault in the Quanzhou are-a.The results show that the displacement rate of the main faults is 3 ~5 mm/a,indicating that the fault zones remain active with the potential for seismic hazard.