HTML University

Science Dept.

Geology and Soils GEO 100 Notes
Gravity - Mass Wasting

1. General Introduction
   1. Crust 3 - 30 Miles Thick

   2. Uniformitarianism : "The Present Is The Key To The Past"

   3. Catastrophism

   4. Streams Most Important Agent of Erosion

   5. 12 Million Years to Wear away Continents to "Base Level"

   6. Internal Forces Create Continents

2. The Agents of Erosion
   1. Mass Wasting

   2. Running Water

   3. Glaciation
      1. Alpine

      2. Continental

   4. Ground water

   5. Wind

   6. Waves

3. Prime Movers Solar and Gravity

4. Downslope Movement - Some Terms
   1. Overburden

   2. Mantle

   3. Colluvium

   4. Slope Retreat

   5. Slope Reduction

5. Downslope Movement - Important Factors
   1. Weathering
      1. Degree of Weathering

      2. Type of Weathering

   2. Water (eg. Climate)
      1. Weight

      2. Bouyant

      3. Lubrication

   3. Frost Action

   4. Slopes 5% to 45%

   5. Angle of Repose:
      1. Size of Particles

      2. Shape of Particles

   6. Vegetation

6. Types of Materials
   1. Earth or Soil

   2. Mud

   3. Rock

   4. Debris

7. Types of Movement
   1. Slow
      1. Creep
         1. Soil

         2. Rock (nb Talus or Scree Slopes)

         3. Rock Glacier

      2. Solifluction - Cold Areas and Permafrost

   2. Fast
      1. Falls
         1. Rock

         2. Debris

      2. Slides
         1. Rock

         2. Debris

         3. Avalanche

         4. Land

      3. Slumping

      4. Flows
         1. Earth

         2. Mud

8. Triggering
   1. Undercutting Slope

   2. Overloading Slope

   3. Vibrations

   4. Additional Water

9. Control of Movement
   1. Dewatering
      1. Surface

      2. Subsurface

   2. Slope Stabilization
      1. Graded Back

      2. Terraced

   3. Protective Fences

   4. Mine Bolts