改良型PS-InSAR測量法求定臺灣中部地區的地層下陷量

Improved PS-InSAR Algorithm for Determining Subsidence in Central Taiwan

楊佳祥(Chia-Hsiang Yang) ； 蔡展榮(Jaan-Rong Tsay) ； 蘇柏宗(Po-Tsung Su)

《航測及遙測學刊》 19卷3期 (2015/01) Pp. 171-187

https://doi.org/10.6574/JPRS.2015.19(3).2

摘要

本文提出改良型永久散射體雷達干涉測量法（PS-InSAR），使用臺灣中部地區的ALOS PALSAR雷達影像來進行PS-InSAR測量，用來求定此區的地層下陷量，此區涵蓋大範圍的植被區和山區，找出此區可用的200個精密水準點資料，與PS-InSAR計算成果進行比較，兩者求定的高程變動速度差值之絕對值，平均值為1.4cm/year，最小值為0.0cm/year，最大值為4.5cm/year，均方根值RMSD為1.4cm/year，考量其顯著性下，兩者測量結果可視為相當吻合。實驗結果驗證了PS-InSAR配合ALOS PALSAR雷達影像在測量臺灣中部地區的地層下陷量之應用潛力，ALOS PALSAR目前已經除役，未來採用品質更好的雷達影像如TerraSAR-X或TanDEM-X，將具有提高PS-InSAR成果品質的良好潛力。

關鍵字

合成孔徑雷達 ； 永久散射體雷達干涉測量 ； 地層下陷

並列摘要

This paper presents an improved PS-InSAR algorithm and preliminary test results on subsidence determination in central Taiwan. PS-InSAR with ALOS PALSAR images is used to evaluate the land surface subsidence in central Taiwan mostly covered by vegetation and mountains. The PS-InSAR results are analyzed and then evaluated by comparing with precise leveling data. Both results determined by PS-InSAR and precise leveling show similar subsidence pattern. The statistic figures derived from the absolute differences in vertical displacement velocity vectors on 200 PSs and 200 benchmarks show that the absolute differences have the mean 1.4^(cm)/year, the minimum 0.0^(cm)/year, the maximum 4.5^(cm)/year and the root mean square difference (RMSD) 1.4^(cm)/year. The conclusion infers that monitoring large-scale subsidence in central Taiwan by means of PS-InSAR is feasible and applicable, and it has a good application potential for a national-level regular subsidence monitoring project particularly with advanced radar data.

並列關鍵字

SAR ； Permanent Scatterers Interferometric Synthetic Aperture Radar (PS-InSAR) ； land subsidence