Mass-Wasting Movement of Large Amounts of Material Downhill under Gravity
Types of Mass Wasting Slow vs. Fast Wet vs. Dry Cohesive vs. Fragmented
Types of Mass Wasting Creep Slow Landslide Earthflow, Mudflow, Debris Flow Avalanche Rockfall Slump Complex Landslide
Factors in Mass Wasting Climate Moisture Steep Slopes Weak Rocks Existing Failure Surfaces
Soil Creep
Soil Creep, California
Creep, North Carolina
Colluvium, San Bernardino Mountains, California
Mystery or Soil Creep?
Four Years’ Mass-Wasting, Bosnia
100*40/2 cm 2 = 2000 cm 2 (4 years) = 500 cm 2 /year Removed from 1 km slope per year = 500 cm 2 /100,000 cm = 1 cm/200 yr = 5000 cm (50 m)/m.y. = 50m /m.y. A 1-m (100 cm) soil mantle yields 500 cm 2 /year, so movement = 500 cm 2 /year/100 cm = 5 cm/year
Debris Flow, Utah
Landslide, Wyoming
Geological Disneyland, Utah
Landslide, Utah
Landslide, Wyoming
Landslide and Slope Control, Wyoming
Landslide, Wyoming
Bridge of the Gods, Washington
Gros Ventre Slide, Wyoming, 1925
Slide Lake, Wyoming
Gros Ventre Slide, Wyoming
Landslide, Pakistan, January 4, 2010
Urban Planning, San Diego
Martian Landslide
Active Landslide on Mars
Rockfalls, Yosemite, California
Block Slide, Yosemite
Rockslide, Yosemite
Slumps? Baird Creek
Avalanche Chute, Colorado
Landslide, Mount Saint Helens
Aberfan, Wales October 21, 1966, a large waste pile from coal mining collapsed Village school was in the path of the slide 144 people killed, 116 of them children Weathering of coal mine waste liberates sulfuric acid and weakens waste piles Seepage beneath pile contributed
Coal Tip, England
Aberfan Slide
Inquiry Board, 1967 the Aberfan Disaster is a terrifying tale of bungling ineptitude by many men charged with tasks for which they were totally unfitted, of failure to heed clear warnings, and of total lack of direction from above. Not villains but decent men, led astray by foolishness or by ignorance or by both in combination, are responsible for what happened at Aberfan.
Sherman Glacier, Alaska, March 27, 1964
Blackhawk Landslide, California
Saidmareh Landslide, Iran
Landslide on Iapetus
Viaont, Italy, October 9, people died.
Yungay, Peru, May 31, 1970
Lituya Bay, Alaska, July 9, 1958
Lituya Bay, Before and After
The Scour Line
The Highest Wave Ever Recorded
Dealing With Mass-Wasting Proper Land Use – Stay out of Danger Take warnings seriously Structural Control – Retaining Structures – Drainage – Terraces Warning System Accept the Risk and Responsibility Abolish Insurance ?