The Application of Borehole Hydrogeological Investigation for Assessing Landslide Susceptibility

Abstract

On the basis of 49 borehole studies at the mid- and upper-stream of the Dajia and Jhuoshuei river basins, landslide occurrence was found to not only be related to subsurface geological composition and hydrogeological characteristics, but also to groundwater level dynamics, which have seldom been addressed in previous works. It is suggested that the interplay between hydrogeologic and landslide factors be given further consideration in future investigations. This would be a crucial step towards effective disaster prevention for mountainous regions in Taiwan.本研究主要係嘗試透過孔內水文地質調查結果，評估大甲溪與濁水溪流域地表下岩層的地質材料特性、水力特性、地下水與集水區山崩潛勢之關聯性。過去研究較少針對崩塌地進行現地水文地質調查與試驗，本研究根據49處試驗場址成果顯示，水文地質特性與山崩的潛勢、滑動深度，以及地下水位有一定程度之關聯性。本研究建議進行調查區域的水文地質特性，以及各促崩因子所造成的山崩的易損性，係各類型山崩災害分析與潛勢評估之重要的研究各題，亦可提供相關台灣災害防治之參考