Archaeologists frequently record location using the UTM coordinate system, which divides the world into numbered zones. The utmZone field captures which zone a Project's coordinates fall in, and it gives the necessary context for interpreting the utmEasting and utmNorthing values — an easting and northing only pin down a spot once you know the zone they belong to. It is optional, so projects that record location only as latitude and longitude, or only descriptively, can leave it blank. When you do use UTM, recording the zone here keeps the project's grid coordinates unambiguous and ready for mapping software.
Technical section
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