Fundamentals of Surveying (FS) Practice Exam

Which of the following methods is used to develop contour lines from irregularly spaced ground elevation points?

1. Barometric leveling

2. Spatial interpolation

3. Vector mapping

4. Field survey measurement

The correct answer is: Spatial interpolation

The method used to develop contour lines from irregularly spaced ground elevation points is spatial interpolation. This technique involves estimating values at unknown points based on the values of known points. In the context of contour mapping, spatial interpolation algorithms can create a continuous surface from discrete elevation data, allowing surveyors to generate contour lines that represent the topography of the land. Spatial interpolation methods, such as kriging, inverse distance weighting, or natural neighbor interpolation, consider the spatial distribution of the known points to make informed estimates about the elevation at other locations. This is particularly useful when the elevation data is collected at varied intervals, as it allows for the accurate representation of the terrain's features. Other methods mentioned, like barometric leveling, are primarily concerned with measuring elevation differences based on atmospheric pressure rather than generating contour lines from existing data. Vector mapping refers to representing physical features as points, lines, or polygons rather than focusing on the elevation or contour generation. Field survey measurement is essential for collecting data but does not directly involve the interpolation process required to create contour maps.