by Marion Constante – Archaeologist & GIS Specialist
Geographic Information Systems (GIS) is used for the archaeology at the Old Colchester Park & Preserve to create visual representations of geographic data that include data collected from surveys, historic documentation, natural features, and modern cultural. Using computer software this data is translated into maps using a variety of cartographic techniques. Examples of some of these techniques are symbology (i.e. color and symbols) to represent features, labels positioned and sized according to the scale of the map and position of map features, and aesthetic elements that draw the attention of the audience as well as represent the purpose of the map. Maps can be produced to show the location of excavations, features, topography and natural features, artifact distributions, and structures both historic and modern. The most common maps are ones that show the location of geographic features such as the location of Old Colchester Park in Fairfax County as seen from the map produced below.This map uses effects to draw attention to the park and county but also show other important features such as roads, rivers, and buildings. To highlight terrain and elevation a shaded relief can be created and used in maps. Cartography does not always need to be in two-dimensions. Using a terrain created from a 1920’s topographic map and mapping the locations and foundations of historic structures in the 18th century town of Colchester, GIS was used to turn the 2D into 3D.