A survey performed to determine if a
structure or object is changing shape or moving. The three-dimensional positions of specific points on an object are determined, a period of time is allowed to pass, these positions are then
re-measured and calculated, and a comparison between the two sets of positions is made.
The relative location of a structure, wall, landmass or any other object can be monitored for movement either horizontally and vertically with respect to a fixed location such as Control Points or
Bench Marks.