In late March 2016 Suffolk Archaeology carried out two Geophysics open days at Garden Field, Sutton Hoo, allowing visitors to the famous National Trust site to learn about how such surveys are carried out. Two types of equipment were used, a magnetometer and a magnetic susceptibility meter …
The project, which was jointly funded by the National Trust had two aims. One was to simply survey the field for archaeological remains, the second was to establish if such a drop-in project was suitable for visitor participation as a part of the Sutton Hoo experience.
The magnetometer survey was eventually carried out twice, once by Suffolk Archaeology staff and once by members of the public. This proved to be important as the visitor’s magnetometer datasets proved to be too 'noisy', due to the high degree of ferrous material present on volunteers clothing affecting the sensitive magnetometer’s sensors! Nevertheless the volunteers enjoyed walking the 20m grids and getting to grips with the principles and methods of carrying out a detailed magnetometer survey.
The magnetic susceptibility survey was carried out by both Suffolk Archaeology staff and site visitors (the equipment not being affected by ferrous material in their clothing). Readings of the level of magnetisation within the volume of earth beneath the sensor were taken every 10m within a grid laid out over the entire field. Higher magnetic readings are commonly indicative of settlement type activity - for example fires, or in this case potential human cremation activity believed to have taken place during the Anglo-Saxon period.
Suffolk Archaeology has now processed the data and is producing a report. The magnetometer survey has identified a range of anomalies indicative of potential Bronze Age, Iron Age or Romano British field subdivisions and a droveway, archaeological pits, and perhaps most importantly the remains of a potential Romano-British pottery kiln.
This image shows an interpreted plot of the magnetometer survey overlying the magnetic susceptibility results. The latter shows that the majority of higher readings (darker grey/black tones) are located on a plateau in the eastern half of the data plot towards an area of known archaeological activity.
Suffolk Archaeology would like to thank the National Trust for their co-operation and help in organising the project.