Magnetometry Survey at West Moor

The geophysical survey was undertaken between 01/04/2025 and 02/04/2025. All geophysical survey work was carried out in accordance with current good practice specified in the EAC guidelines document (Schmidt et al. 2015), as recommended by Historic England, and in the Chartered Institute for Archaeologists' Standard and Guidance for Archaeological Geophysical Survey (2014, updated 2020). Parameters and survey methods were selected that were suitable for the prospective aims of the survey and in accordance with recommended professional good practice (Schmidt et al. 2015). Digital photographs of every survey parcel were taken before, during and after geophysical survey to show any changes to field conditions following the programme of works. The photos were downloaded and stored off site, and relevant examples are included as Plates 1 to 3 in this report. The survey was carried out using a Sensys MAGNETO� MXPDA towed magnetometer system. The cart utilises eight FGM650/3 fluxgate gradiometer sensors mounted upon a frame along with data logging equipment and batteries (see Appendix 2). Data was collected using zig-zag traverses alongside a constant stream of GPS data collected through a Trimble R10 GPS, enabling the collected data to be spatially georeferenced without the need for a pre-determined grid system. The data and measured tracks were collected through the data acquisition unit MXPDA and visualised through a tablet PC mounted to the cart. A total of 30.2 ha were surveyed using the Sensys cart. Care was taken to attempt to avoid metal obstacles present within the survey area, such as metal objects within and adjacent to the survey area as gradiometer survey is affected by 'above-ground ferrous disturbance' and avoiding these improves the overall data quality and results obtained. The data was downloaded via USB and converted using DLMGPS and Geoserver before being processed in Terrasurveyor software. The details of these processes can be found in Appendices 2 and 3. Interpretations of the data were created as layers in ArcGIS Pross and the technical terminology used to describe the identified features can be found in Appendix 4. In assessing the results of the geophysical survey against the specific aims set out in Section 4: The survey has succeeded in locating, recording and characterising surviving sub-surface remains within the Site, though more remains may be present that are not suitable for detection using magnetometry; The survey will help in determining the next stage of works as it has provided evidence that remains of an uncertain origin are most likely present on site, and has provided a number of targets for further investigation; The survey has resulted in a comprehensive report and archive.