Black and white structures similar to that shown here, are found up and down the motu (island). What is the relationship between building/construction and these structures? What are they known as? Where are they most commonly found? Why are they important?
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The black & white structures are triangulation stations but are more commonly refered to as trig stations/points. Set up by the government usually on hilltops so they are more visible, with their coordinates & elevation made public, they are fixed surveying stations used in geodetic surveying.
ReplyDeleteThey are usually found in a group to form a triangulation, which allows buildings & constructions to be accurately located & for monitoring of precision & accurate building on a construction site. Sometimes the construction company can even erect a temporary station on site so that they can monitor their accuracy more closely.
They are important as they provide a set of control marks that can be physical reference points from which the building industry can ascertain data such as latitude & longitude, & therefore location of property boundaries in relation to official geodetic data.
They can come in many shapes & sizes but are all providing the same information.
http://www.linz.govt.nz/geodetic/find-out/trig-stations/images/trig-station.jpg
ReplyDeleteThe physical component of New Zealand's geodetic system is a network of control marks that serve as physical reference points. A number of these marks are black and white trig beacons, seen on the tops of hills, or steel pins set into concrete in urban areas. These marks are used by surveyors to determine the location of property boundaries in relation to the official geodetic datum. Thousands of vital survey marks exist in New Zealand. Many of them are below or at ground level and not noticed by most of us