EOSC 114: Landslides Learning Goals
EOSC 114: Landslides Learning Goals
1. Explain how the socioeconomic impact of landslides depends on the type and characteristics of the landslide hazard.
2. Distinguish between the different modes of failure (falls, flows, slides, topples, and spreads) and how they are influenced by geology.
3. Define the chief components of landslide risk. 4. Compare and contrast landslide causes and how they differ from landslide triggers.
5. Assess the balance between the strength of the slope and the destabilizing forces due to erosion, vegetation, precipitation, and anthropogenic activity that are acting on it (Factor of Safety).
6. Describe how groundwater affects shear stress and shear strength, and how it contributes towards the increased likelihood of a landslide.
Impact depends on vulnerability to landslides: -high population density (close to mountains) -use of land (crops, agriculture destroyed?) -rapid land-use change (mining, blasts) -global warming (change weather patterns) Fall: drop vertically, gravity Flow: mess of soil, rock etc. flowing down slope (not as coherent mass) a) Creepflow that moves very slowly b) Debris flowrapid flow of saturated debris, travel in narrow gorge and fan out at bottom—common in BC b/c rain c) Debris avalanche rapid flow of semifully saturated debris, not contained to channel (spreads out) Slides: a) Rotational soil/rocks slides down curved surface b)Translationalstrong blocks of rock move down faulted plane (flat angle) Topples: falling of solid, coherent blocks that rotate around a point in the air Spreads: (lateral)spread of soil, rock, usually b/c of liquefaction
Causes: build up to the landslide Trigger: causes the landslide to actually happen -Earthquake -Volcano -Precipitation -Anthropogenic activities Factor of Safety (FS) = = So when FS >1, slope is stable. FS
1. Explain how the socioeconomic impact of landslides depends on the type and characteristics of the landslide hazard.
2. Distinguish between the different modes of failure (falls, flows, slides, topples, and spreads) and how they are influenced by geology.
3. Define the chief components of landslide risk. 4. Compare and contrast landslide causes and how they differ from landslide triggers.
5. Assess the balance between the strength of the slope and the destabilizing forces due to erosion, vegetation, precipitation, and anthropogenic activity that are acting on it (Factor of Safety).
6. Describe how groundwater affects shear stress and shear strength, and how it contributes towards the increased likelihood of a landslide.
Impact depends on vulnerability to landslides: -high population density (close to mountains) -use of land (crops, agriculture destroyed?) -rapid land-use change (mining, blasts) -global warming (change weather patterns) Fall: drop vertically, gravity Flow: mess of soil, rock etc. flowing down slope (not as coherent mass) a) Creepflow that moves very slowly b) Debris flowrapid flow of saturated debris, travel in narrow gorge and fan out at bottom—common in BC b/c rain c) Debris avalanche rapid flow of semifully saturated debris, not contained to channel (spreads out) Slides: a) Rotational soil/rocks slides down curved surface b)Translationalstrong blocks of rock move down faulted plane (flat angle) Topples: falling of solid, coherent blocks that rotate around a point in the air Spreads: (lateral)spread of soil, rock, usually b/c of liquefaction
Causes: build up to the landslide Trigger: causes the landslide to actually happen -Earthquake -Volcano -Precipitation -Anthropogenic activities Factor of Safety (FS) = = So when FS >1, slope is stable. FS
