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Engineering Geology - Coggle Diagram

- - - - Building collapse
      - Ground Liquefaction
        
        soil substantially loses strength and stiffness
        
        Due to an applied stress such as shaking during an earthquake
      - Fires
      - Landslides
    - - Minimum standards for reinforced concrete
      - Safety glass to replace conventional glass in skyscrapers
      - Retrofitting foundations with rubber dampeners
      - Smart values to turn off oil/gas supplies when Earthqukes occur
      - Use of bolts to pin walls to floors
        
        Reduce chance of 'pancaking'
        
        collapse occurs from the top-down
        
        Upper floors collapse down onto lower ones, causing collapse
      - Fasteing of major appliances to walls to prevent movement
        
        E.g. fridges, TVs
      - Deep foundations into solid bedrock
        
        Not affected by liquefaction
      - New building's with lower center of gravity
      - Avoid building on areas prone to liquefaction during Earthquakes
        
        Avoid building on:
        
        Reclaimed land
        
        marshes
        
        Old lake beds
        
        River floodplains
      - Computer-controlled weights on the top of skyscrapers to counter any swaying caused by a seismic event
      - Floors able to slide horizontally on muli-storey buildings
        
        Through the use of a rack and pinion device and teflon (non-stick) coated materials on the base/top of floors
      - Reinforce weak points in infrastructure to ensure they are Earthquake resistant
        
        Tunnels
        
        Bridges
        
        Flyovers
        
        Freeways/Motorways
    - - Hazard Interval Patterns (Seismic Gaps)
        
        Seismic Gaps in time
        
        Long time since Earthquake at a certain part of the Boundary (compared with other segments along the same boundary/structure)
        
        Seismic event more likely
        
        Seismic gap in space
        
        Long time since Earthquake around/near to a certain part/segment of the Boundary (compared with other segments along the same boundary/structure)
        
        (At Segments of an active fault known to produce significant earthquakes)
        
        Detailed record of past seismic events
        
        With dates
        
        Can be used to calculate an average resurgence interval for a seismic event over a certain magnitude
        
        With locations
        
        Areas that haven't expericnced seismic events for a long time/at all are more likely to have the next seismic event
  - - - Lava flows
      - ash fall
      - Pyroclastic flow
      - Lahars
    - - Implementing building restrictions in areas prone to eruptions
    - - Measuring Ground deformation
        
        using tiltmeters
        
        Measure minute changes the angle of the Earth's surface
        
        ground increasing in tilt/bulging over time
        
        Magma moving towards surface
        
        land fails
        
        major Earthquake
        
        1 more item...
      - Groundwater changes
        
        Monitor in Boreholes:
        
        Water chemistry
        
        Water levels
        
        Falling water levels, increase in dissolved radon gas
        
        Sometimes occur before major seismic event
        
        Temperatures
        
        Increased Temp.'s , increased dissolved sulphur dioxide, increased carbon dioxide
        
        Magma moving towards surface
        
        May lead to volcanic eruption
        
        1 more item...
      - Gas emissions
        
        Correlation spectrometers (COSPEC) around active volcanoes
        
        rapid carbon dioxide and Sulphur dioxide emission increase just (24-48hr) before eruptions
  - - - Buildings on stilts in areas prone to tsunamis
        
        Allow water to flow underneath
      - Planting of mangroves in coastal areas prone to tsunami
        
        Mangroves absorb the force of the waves
  - - - (slope collapse)
  - - - Bulldozers, JCBs, cranes, fire engines
      - Doctors, paramedics, hospitals
      - heat-seeking equipment, sniffer dogs
  - - - Increased pop. density = increased casualties
    - - Aseismic desgn
      - Early warning systems
      - Rapid response emergency services
      - In MEDC's and HEDC's
    - - High risk areas
        
        Parks, Golf couses, ect.
      - Low risk areas
        
        Hospitals, schools, ect.
      - Intermediate risk areas
        
        Houses, commerical
    - - lack of PCs, broadband, political will
        
        Warnings poorly communicated
        
        Increased casualties
        
        In LEDC's
        
        (Least/Less Economically Developed Countries)
    - - as they lack money to invest on Disaster prevention
      - More pressing matters occupy resources (e.g. shelter, education, health care)
    - - Earthquake drills
        
        Decreased casualties
      - Clear Evacuation routes
      - Early warning
- - - - Domestic
        
        Household waste, garden waste, ect.
      - Hazardous
        
        Medical waste, industrial waste, radioactive waste
        
        Waste that needs special disposal
    - - Impermeable rock types
      - Permeable rock types
        
        Site must be made impermeable through Engineering
        
        Clay linings
        
        Artificial geomembranes
        
        (Type of textile sheet to prevent seepage from waste disposal site)
  - - - Leechate
        
        r the liquid pollution that seeps through a landfill's waste pile when it rains or snows
    - - ensure that water quality is
        of an acceptable and safe standard
      - Ensure not contaminated
  - - - underground in impermeable rocks
        
        (e.g. as in disused salt mines)
      - at the surface in secure repositories
  - - - Remove/harvest
        
        treat so that they are safe
      - bioremediation
        
        process that uses mainly microorganisms, plants, or microbial or plant enzymes to detoxify contaminants in the soil and other environments
- - - - Dams
      - Reservoirs
      - Cuttings
        
        Rock fact cut out for road, rail, ect.
      - Tunnels
    - - Mechanically strong
        
        Can support steep slopes
        
        e.g. limestone, sandstone, granite
      - Mechanically weak
        
        Unable to support steep slopes
        
        collapse/slump after periods of high rainfall
        
        slope failure
        
        e.g. clay, mudstone, shale
    - - Permeable
        
        Absorbs water
        
        Increases in mass
        
        increases pore water pressure
        
        the pressure experienced by water trapped in pores
        
        slope failure
    - - Faults and joins common
      - Fault reactivaton may occur
        
        Fault may reopen due to stress, think 'structures' unit
        
        Expensive engineering solutions to re-stabilize area
    - - Strata dips down towards excavation
        
        Expensive slope stabilization
        
        Or slope failure
      - Strata dips down away from excavation
        
        Naturally stable
    - - Rock bolts
      - shockcrete
      - Gabion baskets
      - Slope re-profiling
      - Drainage