GEOL 2207 Lecture Notes - Debris Flow, Quick Clay
Document Summary
Compare and contrast landslide causes and landslide triggers: cause factors leading to instability, triggers translate instability into motion. List and describe several external causes of landslides: high slope angle, undercutting, overloading, vegetation, climate. List and describe 3 internal causes landslides: water in slopes. Decreases normal force/normal stress which decreases friction and thus, shear strength. Acts as a medium for flows: water in sediment. No water = low angle of repose, some water = high, too much water = very low angle: water in solid rock. Water reduces shear strength along planes of weakness. Frost wedging, water gets into cracks and fractures in rocks freezes and expands forcing fractores apart: inherently weak materials. Quick clay slides not common: adverse geologic structures. List several landslide triggers: earthquakes, snow melt, heavy rainfall, rain on snow, loud noises, vehicles, volcanic eruptions, excavation, skiing, jumping up and down.
