本計畫以三年為期,選定霧社水庫上游集水區為研究區域,透過大規模崩塌之判釋、調查、活動 性監測、崩塌塊體分塊分群及地表變形資料反演逆推崩塌潛在之滑動面,進而推求研究區域內潛在 土砂生產量,以為本計劃其他子計畫進行河道土砂侵淤模擬之用。 本計畫第一年工作涵蓋研究區域之地文與水文資料蒐集、光達數值地形之細部判釋與分析、結合 現地地質與坡地崩塌地形特性之調查,以了解研究區域大規模崩塌發生潛勢區位之位置與規模。此 外,藉由 ALOS 與 ALOS2 L 波段之雷達影像,利用 TCP-InSAR 分析技術,了解大規模崩塌發生 潛勢區位內之變形速率進而作為評估其活動性之指標。第二年工作將選擇特定案例,藉由多時序變 形速率之變異,討論崩塌之分塊與分群,同時透過得知之地表變形數據,進行地表變位之逆推反演, 以推求可能之潛在滑動面進而得以計算其可能之土砂生產量體。第三年則將相關發展之技術應用於 集水區其他大規模崩塌潛勢區域,以評估研究集水區內大規模崩塌產生之可能產生之土砂量並為其 他子計畫進行土砂運移及入庫土砂量評估之參考與依據。 本研究將為國內外極為少數量化評估集水區內大規模崩塌潛勢區位可能產生之土砂生產量,相關 成果將為相關單位在大規模崩塌災害防治工作後續作為之重要參據。
In this three-year project, the watershed of Wushe Reservoir is selected as the study area. The potential debris induced by deep-seated landslides will be evaluated after the sliding plane is inferred from surface deformation by using the inversion of dislocation model. Debris inferred from the inversion will be used to simulate sediments yield of landslides of the study watershed in other projects. In the first year, basic information of the study watershed will be collected. Deep-seated landslides will be identified through morphtectonic interpretation of LiDAR derived 1 m resolution DEM. In addition, surface deformation related to the movement of deep-seated landslides will also be calculated by using ALOS images through TCP-InSAR analysis. In the second year, specific deep-seated landslides will be selected to identify their active portions through multi-temporal deformation analysis. In addition, potential sliding surface will be inferred from the inversion of surface deformation, which shall be induced from TCP InSAR analysis. In the last year, debris derived from important deep-seated landslides within the study area will be calculated, in order to estimate the total amount of debris that may be present during extreme climatic conditions. Results of proposed study will provide quantitative estimation of debris induced by deep-seated landslides. It is very important information for the mitigation of deep-seated landslides hazards and watershed sediments yield.