Landslides

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Landslides

• Geology 2022 Natural Disasters
• Department of Geography Geology
• Nipissing University
• Autumn 2007

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Review Debris Flows Avalanches

• a) Slopes as hazards
• b) Slope Failures
• c) Classification
• (see figs. 10.16 10.17)

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Review Debris Flows Avalanches

• d) Debris Flows
• e) Snow Avalanches

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Introduction Landslides

• a) Defn
• A mass of unconsolidated earthen material
  sliding down an identifiable sliding plane
• b) Slope Failure
• i) Gravity
• ii) Conditional Stability
• iii) Causes Triggers
• (internal external)

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Introduction Landslides

• c) Importance
• i) Economic Losses
• ii) Human Losses
• d) In Canada
• i) Canada Landslide Project
• (http//gsc.nrcan.gc.ca/landslides)

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Causes

• a) Internal Causes
• i) Weak materials
• (see fig 10.7)

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Landslides

• a) Internal Causes
• ii) Pore water pressure
• iii) Decreases in cohesion
• iv) Geologic structure
• (e.g. dipslopes see fig 10.12a)

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Landslides

• b) External Causes
• i) Slope steepening
• ii) Removal of support
• iii) Adding mass
• iv) Degradation
• (e.g. deforestation)

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Landslides

• c) Triggers
• i) Precipitation Events
• (NB. intensity duration)
• ii) Undercutting
• iii) Seismic Activity
• iv) Volcanic Activity
• iv) Human Activity

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Landslides

• d) Types
• i) Rotational
• (see fig 10.6 a b)

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Landslides

• d) Types
• ii) Translational
• (see fig 10.25)

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Management

• a) Land-use Planning Management
• b) Conservation Practices
• c) Co-ordinated Remedial Measures
• d) Monitoring
• e) Early Warning Systems
• f) Research