本研究的研究區域庫曼(Kumaun)位於印度西北部北阿坎德邦(Uttatakhnad Pradesh)的喜馬拉雅山脈(Himalaya)南段。本研究目的為探討由南而北分別為恆河平原(Ganga Plain)、希瓦立克(Siwalik)以及小喜馬拉雅(Lesser Himalaya)地區的地表變形。希瓦立克區域是喜馬拉雅山脈的變形前緣並以HFT (Himalayan Frontal Thrust)為南界，MBT (Main Boundary Thrust)為北界。由於本區域內缺乏大地測量等觀測網，因此主要使用InSAR (Interferometry Synthetic Aperture Radar, 雷達差分干涉)方法，再搭配在區域內架設的12個移動型GPS (Global Positioning System, 全球衛星定位系統)觀測站以及全站儀來測量區域內的地表變形。使用的影像與觀測時間段分別為EnviSAT衛星2008年至2010以及ALOS衛星2007年至2010年。除此之外，亦使用不同的方法對EnviSAT影像做大氣延遲校正(TRAIN軟體)。本研究中使用ERA模型以及MERIS衛星資料對影像做校正。由於缺乏前人的觀測以及研究，本文的GPS及InSAR資料為本區域內最早的衛星測地結果，並能夠運用於未來做更進一步的研究。結果顯示，雖然本區域極少發生地震事件，但在區域內的一些構造線兩側卻呈現出不同的變形行為。本文提出簡易模型以說明此區域的斷層構造演化：此區域中央高四週低的地形，應是由於右移斷層Garapani-Kathgodam Fault西側區域移動方向與多數逆衝斷層相反，導致此區域沿著Ramgarh Thrust (RT)南緣抬升，LOS速度約10至30 mm / yr；而RT以北的區域下降，LOS速度約-10 mm / yr。由本研究觀測的測地速度做初步判斷，此區域斷層淺部有耦合的可能，在未來有可能孕震。;The Kumaun area is a part of the Himalayan mountain belt that locates at the Uttarakhand Pradesh, northwest India. In this study I focus on the deformation of "Ganga Plain", "Siwalik" and "Lesser Himalaya" areas, from south to the north. Siwalik is the deformation front of the Himalayan orogene bounded by HFT (Himalayan Frontal Thrust) to the south and MBT (Main Boundary Thrust) to the north. Since there was no geodetic network in this area, our research group installed 12 campaign GPS stations and total station nets in the area. I also used InSAR (Interferometry Synthetic Aperture Radar) technique to observe surface deformation of this area. I used EnviSAT images from 2008 to 2010 as well as ALOS image from 2007 to 2010 to carry out a series of analysis. Additionally, I also tried some methods (TRAIN software) to correct the atmospheric effect. ERA and MERIS data are used to correct the atmospheric delay in this study. As a result of lacking seismic data and others geodetic measurement in the region, my InSAR and GPS measurements are the first dataset to reveal the different deformation patterns along some geological structures, and can be applied to further reaserches. Despite few seismic events have occured in the area, our observations revealed that some of the areas that nearing the faults have been experiencing obvious deformation during the observation period. I hereby propose a model to interpret the tectonic evolution in Kumaun Himalaya. The highest terrain located in the center of area appears to be caused by the opposite movement between Garapani-Kathgodam Fault (right-lateral fault) and the others thrusts, which make the area in the south of Ramgarh Thrust (RT) uplifted with observed LOS velocities of about 10 to 30mm/yr. Area in the north of RT, on the other hand, is subsiding with a LOS velocity about -10mm/yr. Our geodesy results indicate that the shallow part of faults in study area coupled thus implies a potential of earthquake rupturing in the future.
