Why Is an Imaginary Grid So Important to Archaeologists?

Archaeologists lay out grids to record where artifacts were found in relation to each other.

Digging a site destroys it forever. Archaeologists record where each artifact is found by noting its position on a grid--not only to aid their future laboratory work, but for future archaeologists who will no longer have access to the site.

Grid Setup

An arbitrary point on the southwest corner of the site is chosen to be point (0,0). Then stakes are driven into the ground a meter apart north and east of point (0.0). These stakes form the X and Y axis of a Cartesian coordinate system. Depending on the site, more stakes are driven or twine is actually strung to mark off individual meter-by-meter squares.

Record Keeping

When artifacts are found, their location is recorded in the meter-by-meter coordinate system. If it is a small artifact, the location within the meter square may be recorded by referencing the southwest corner of the square. The time and the finder are also recorded for the excavation of each square.

In the Laboratory

In the laboratory, after the dig is over, the artifacts are reconstructed using the grid map. If there is a question about an artifact, the person who excavated the square where the artifact was found is consulted.

References

• Archaelogy: Grids
• CSI: Archaelogical Grids
• LearnNC: Gridding a Site