Magnetic survey measures the variation of magnetic fields of the earth and buried features across a site. Different soils and features can be mapped through their contrasting magnetic values. Examples of features that can be detected through this process include ferrous materials (iron, etc.), soil affected by human occupation (trash pits and middens with organic materials), fired materials such as kilns and hearths, tiles, bricks, and concentrations of ceramics. Differences in soil type or disturbed soil are also detected through magnetic survey enabling identification of ditches, pits, foundations, graves and other excavated features.
See What Meg Sees: Instructions for Interpreting the Data
Using the tool below, click on individual grids for a closer look at the Magnetometry data Meg and her team gathered at the Dillard site. You can toggle between an arieal view of the landsape, the map of the data only, and then read Meg's interpertation of each of the data points as you learn more about what each grid reveals. Each grid you click on will become highlighted.