##  [Geographic Coordinate](/geographic-coordinate-0) 

 Definition

A numeric coordinate pair or set (e.g., latitude and longitude, or projected easting/northing) that specifies a location on the Earth's surface within a defined geodetic reference system and projection, including the datum and epoch when required for unambiguous positioning.

 

 

 

 

 

 





## Principle

Principle

A geographic coordinate is unambiguous only when accompanied by its geodetic reference system (datum), projection (if projected), and units; these metadata are required to transform, map or integrate coordinates reliably.

 

 

 

 

 





## Demonstration

Demonstration

Illustrative scenario: Situation — An artifact is recorded with coordinates. Recognition — The recorder notes '37.1234°N, 2.3456°W, WGS84 (EPSG:4326)'. Action — GIS staff import the point using the specified CRS and overlay it on regional maps. Consequence — The location aligns correctly with other georeferenced datasets because the reference system and units were documented.

 

 

 

 

## Misapplication

Misapplication

Entering latitude/longitude without specifying the datum or confusing decimal degrees with degrees/minutes/seconds; the semantic error is assuming numeric coordinates are self‑sufficient identifiers of place rather than values that require a reference system to be meaningful.

 

 

 

 

 





## Consequence

Consequence

Missing or inconsistent coordinate metadata produces mislocated points after reprojection, map misalignment, inability to integrate datasets, and potential misinterpretation of spatial relationships at site and landscape scales.

 

 

 

 

## Reversal

Reversal

For fine‑grained intra‑trench recording, local grid coordinates tied to a site origin may be preferable to global coordinates because they provide higher local precision and legibility for excavation staff; however, to situate the site regionally the local coordinates must be related to geographic coordinates via survey ties.

 

 

 

 

 





## Boundary

Boundary

Clearly within: a coordinate pair with an explicitly stated datum and projection. Boundary case: numeric coordinates recorded without datum noted. Clearly outside: verbal place descriptions or relative directions without numeric coordinates.

 

 

 

 

 





## Semantic Tension

Semantic Tension

Global interoperability and locateability ↔ local measurement precision and operational convenience of site‑centric coordinate systems.

 

 

 

 

 





## Synthesis

Synthesis

Geographic coordinates place field observations within a global spatial framework, but they become operationally useful only when the supporting geodetic metadata (datum, projection, units) are recorded so coordinates can be transformed and integrated without ambiguity.