DRRR4

• Geological Map


  It shows how geological features, rock units or geologic strata are shown by colors or symbols to indicate where they are exposed at the surface
• Geological Map Features


  • Faults
  • Tilts
  • Folds
  • Rock layers
• Parts of Geological Map


  • Legend
  • Interpretation
  • Title
  • Susceptibility
  • Sources
• Symbols in Geological Maps


  • Thick lines and thin lines
  • First capitalized letter in geologic unit
  • Colors
  • Dotted contact line
• Symbolizing Geology


  • Contours and topography are just the first parts of a geologic map
  • The map also puts rock types, geologic structures, and more onto the printed page through colors, patterns, and symbols
• What can you see in a Geologic Map


  • Shoreline
  • Roads
  • Towns
  • Buildings
  • Borders
  • Contours
  • Various water features
• Geologic Age and Formation Symbols


  • The letter symbols signify the name and age of the rock units in an area
  • The first letter refers to the geologic age
  • The other letters refer to the formation name or the rock type
• Many age terms begin with P that special symbols are needed to keep them clear
• The Cretaceous Period is symbolized by the letter K, from the German word Kreidezeit
• The meteor impact that marks the end of the Cretaceous and beginning of the Tertiary is commonly called the "K-T event"
• Other letters in a formation symbol usually refer to the rock type
• The second letter might also be an age term, particularly in the Cenozoic
• The real beauty of geologic maps is in their colors
• In late 1800s two traditions arose: the harmonious American standard and the more arbitrary International standard
• Every geologic map has its reasons to deviate from the standards
• Geologic maps, especially the kind still printed on paper, represent a dialog between truth and beauty
• Very High Landslide Susceptibility


  • Areas usually with steep to very steep slopes and underlain by weak materials
  • Recent landslides, escarpments and tension cracks present
  • Human initiated effects could be an aggravating factor

  
• High Landslide Susceptibility


  • Areas with steep to very steep slopes and underlain by weak materials
  • Areas with numerous old/inactive landslides

  
• Moderate Landslide Susceptibility


  • Areas with moderately steep slopes
  • Soil creep and other indications of possible landslide occurrence are present

  
• Low Landslide Susceptibility


  Gently sloping areas with no identified landslide

  
• Debris Flow or Possible Accumulation Zone

  Areas that could be affected by landslide debris

  
• Symbols and its Interpretation


  • Symbols shown in the image
• Susceptibility


  Landslide susceptibility levels shown in the image