This little section is included because I have lost a couple of years of my life due to a confusion about mapping coordinate systems. I was given a map and when I placed the concession boundary it appeared that the mineralized target was on someone else’s property. How to explain that one to the boss!! It turned out that the map and the property boundary were not in the same coordinate system and so there was a displacement of one relative to the other.

There are probably hundreds of different coordinate systems which attempt to represent the curvature of the earth on flat map surfaces. Every once in awhile, usually in response to better measuring instruments, someone comes up with the “better mousetrap”. The problem is that everyone has been using the older versions of the coordinate systems and so there is lots of room for error during the transition to the new system. The recommended approach is to use the coordinate system in which most government maps have been prepared and ensure that whoever subsequently makes maps or plans for the project identifies the coordinate system used for the map.

If there is a desire to convert the project data to a different map base later in the project there is an abundance of computer software to do the conversion quickly and accurately. Identification of the coordinate system and map datum is an important element to the project design basis. And this information must be widely disbursed to anyone working on the project. Be forewarned!