台灣北部的臺北盆地為人口密集、高度開發建設區域且為台灣現今政治經濟中心，西有山腳斷層，為此區域最主要的活動斷層；北有近期研究重點的大屯火山群，因此對於此區域的地表變形監測乃現今重要之課題。 雷達差分干涉技術為快速有效且全面的地表變形監測工具，已被廣泛應用。但傳統差分干涉技術(DInSAR)對同調性較低的空間及較長時間的基線有其測量限制。因此本研究利用永久散射體差分干涉技術(PSInSAR)，對2007年1月至2011年3月共17幅ALOS所擷取的雷達影像進行北台灣地區地表變形觀測。研究結果顯示台北盆地及大屯火山區中心的地表運動以靠近衛星方向移動為主，其中盆地每年最高以4公厘速度往衛星移動，大屯火山區每年最高以8公厘速度往衛星方向移動。而盆地與火山間山區至基隆河一帶則是以遠離衛星方向移動為主。將本研究成果與GPS資料及精密水準測量進行比對，結果吻合程度高，證實資料可信度。為有效結合GPS及PSInSAR觀測資料，本文透過三角網格進行線性內插，以求取研究區域的三分量速度場。結果顯示大屯火山群至基隆火山群一帶相對於林口台地抬升，且此區跨山腳斷層有明顯的垂直斷層走向的水平運動，推測與地底熱液作用有關。 ;The triangular-shaped Taipei basin locates in the northern Taiwan and has been developed into the most densely populated area and also the capital of politics and economics in Taiwan. Taipei basin is well developed and amenable to research gathering using the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique but the mountainous areas surrounding the basin are mostly covered with densely vegetations that reduce the signal-to-noise ratio in the InSAR interferograms. In this study, we aim to measure the ground deformation of northern Taiwan by processing the spaceborne radar interferometry data of ALOS acquired from 2007 to 2011 using the PSInSAR technique. The mean Line of Sight (LOS) velocity field of up to 8 mm/yr in the central Tatun volcanic area was measured, and up to 5 mm/yr inside the Taipei basin with higher rates at the hanging wall of the Sanchiao fault than the footwall was also revealed. We also integrated GPS and PSInSAR measurements to resolve a three-domensional ground motion across the study area. The result shows that the Tatun volcano and Keelung areas have experienced ground uplift, with notable horizontal extension across and perpendicular to the northern Sanchiao fault. This motion may relate to the subsurface hydrothermal activities beneath the Tatun area.
