深層重力邊坡變形(Deep-Seated Gravitational Slope Deformation， DSGSD)為具依時性的長期坡體變形過程，反映區域地質構造控制與局部邊坡破壞間的密切關聯。雖然DSGSD發育緩慢，但其空間幾何型態與分布常受區域構造強烈束限，進而影響邊坡不穩定的發生位置與型式。因此，釐清區域地質構造、DSGSD型態與局部邊坡破壞三者之關係，對大尺度邊坡穩定性評估具關鍵意義。 本研究以臺灣南投縣仁愛鄉廬山層板岩為主的區域為對象，其以大型複向斜構造為主要特徵並使岩體劈理呈中至高角度傾斜。區域尺度上，褶皺與斷層相關組構提供控制DSGSD空間分布與型態的力學異向性與運動學條件；中尺度上，DSGSD主要表現為受坡向與劈理位態關係控制的岩體變形；局部尺度上，邊坡破壞多集中於DSGSD較破碎區域。 利用高解析度光達坡度圖判釋地貌特徵與線型構造，並進行系統性空間分析，結果顯示判釋之線型與引致構造發育之大地應力方向呈力學相符；坡頂與坡面之崩崖和線性陷落可視為深層破壞累積與漸進式剪裂帶發育至地表之地貌特徵。依文獻提出之DSGSD演化階段分類，鄰近眉溪斷層之場址皆已演化為部分崩塌或崩塌階段；五處場址尚未發育成崩塌階段，且仍可觀察到持續發育中的崩崖及線性陷落特徵，顯示研究區仍處於活躍的漸進式變形狀態。崩崖比(Scarp ratio)介於3%至32%，就已發展為部分崩塌階段之邊坡而言，約達 8%的崩崖比可視為目前研究案例中形成連續深層滑動面之初步指標。局部邊坡破壞分析指出，歷史崩塌面積比例與復發次數相對較高者，多屬順向坡，顯示坡向與劈理傾向接近一致的順向坡拱彎褶皺型、葉理高傾角折彎褶皺型及斷層型重力邊坡變形型態，較易於近地表處發生破裂引致局部破壞。綜上，DSGSD為區域地質構造與局部邊坡破壞之間的關鍵中介，多尺度解析整合地貌指標，可作為評估坡體漸進式變形與潛在不穩定性之實用方法。;Deep-seated gravitational slope deformation (DSGSD) represents a time-dependent rock mass deformation process that links regional geological structures and local slope failures. Although DSGSD develops slowly， its evolution is strongly controlled by tectonic structures and governs the spatial occurrence of slope instability. Clarifying the relationship between regional geological structures， DSGSD types， and local failures is therefore critical for large-scale slope stability assessment. This study investigates DSGSD in a slate-dominated region of central Taiwan characterized by a large synclinorium with moderately to steeply dipping cleavages. At the regional scale， folds and fault-related fabrics provide mechanical anisotropy and kinematic conditions controlling the spatial distribution and types of DSGSD. At the intermediate scale， DSGSD manifests as rock mass deformation controlled by the relationship between slope orientation and cleavage attitude. At the local scale， slope failures preferentially occur within zones where DSGSD-related damage is more developed. High-resolution LiDAR slope maps were used to delineate geomorphic features and lineation structures， enabling systematic spatial analysis. The results indicate that the interpreted lineation structures are mechanically consistent with the regional stress field that governed the development of geological structures. Scarps and linear depressions identified at crown and mid-slope positions are interpreted as surface expressions of deep-seated shear zone development. According to DSGSD evolutionary stage， all sites adjacent to the Meihsi Fault had progressed to the partial collapse or collapse stages. Five sites have not yet developed into collapse stage， and five sites exhibit actively developing scarps and linear depressions， indicating ongoing progressive deformation. Scarp ratio values range from 3% to 32%， for partial collapsed slopes， a scarp ratio of approximately 8% may be regarded as a preliminary index， corresponding to the formation of continuous deep-seated sliding surfaces. Local slope failure analysis indicates that historical landslide area ratio recur most frequently and over larger extents on dip slopes， suggesting that dip slopes with slope orientation is broadly consistent with the cleavage dip are more prone to near-surface fracturing， particularly in buckling-fold， bending-fold and fault-like DSGSD types. These results demonstrate that DSGSD acts as a key transitional process linking regional geological structures and local slope failures， and that multi-scale interpretation combined with geomorphic indicators provides a robust framework for understanding progressive rock mass failure mechanisms.
