Practical Archaeology Course: Gradiometer survey at Down Farm, Dorset

We recently completed a survey as part of the Practical Archaeology Course at Down Farm, Dorset. Following on from previous work, we surveyed an area south of the excavation to help place it in a wider context. This is the result of our day's work (the area was about 180m wide by 120m, and 1.3ha or just over 3 acres in size; click for a larger image):

Down Farm Gradiometer Survey

The site is thought to be an Iron Age farmstead, and excavation has shown that a large ditch surrounds the settlement. Unfortunately, this doesn't appear in the geophysical survey! A modern trench for an electricity cable can be seen running from bottom-left to top-right, and some other anomalies are clear, showing as small dark blobs. The straight lines in the lower half of the results show where ploughing has disturbed the natural soil under the site, and the stronger line near the bottom may mark the limit of historic ploughing.

Until all of the information from the excavation has been entered into our computers, we can't be sure why the ditch doesn't show in the geophysical survey. It's possible that the ditch lies entirely in the area we couldn't reach because of the excavation, shown as the blue area at the top of the image. We'll keep you posted!