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Coordinate Marking Accuracy

Many land surveyors are comfortable with a sharp, "accurate" tip on the end of the survey rod,
and some new surveyors may not even be familiar with other types of shoes or blunt tips.

Occasionally, the accuracy of the 1" diameter PointSpotter paint spot comes into question.

Keep in mind that the natural movement of land surfaces often exceeds the diameter of any survey marker.

Soil and Pavement are Dynamic

• Expansion and Contraction due to MOISTURE CONTENT
  Some more expansive soils are so active, structures on them require some form of isolation from soil expansion.
  During low rainfall, contractive forces are so great that large ground cracks will form, some wider than the survey marker.
  
  
• Expansion and Contraction due to TEMPERATURE
  Temperature affects pavement, thus requiring slotted, periodic expansion gaps to prevent stress and strain.
  
  
• Expansion and Contraction due to VEGETATION DENSITY
  The roots of plants and trees expand and shift surrounding ground, and also influence the soil moisture content.
  
  
• Movement due to EROSION
  Water and ice will cause entire acres of land to shift or slide unnoticed.
  
  
• Rise and Fall due to GRAVITY
  "Solid-body tides" (ground tides) caused by the Moon and Sun displace the ground almost one foot vertically, twice each day.
  
  It is common to forget about types of terrain outside of your surveying experience.
  Remember that there are paved cities, swamps, glaciers, deserts, tropics, plains, mountains, seabeds, and caves... all of them
  surveyed, and all of them in continual movement.