A temporary grid system was established over the site and marked out using canes. The location of the grid was set out using an RTK GPS system theoretically accurate to some 0.01m and referenced to OS co-ordinates. Data was collected using a cart carrying four paired Bartington magnetic sensors. Four sensors mounted 1m horizontally apart and very accurately aligned to nullify the effects of the earth's magnetic field. Readings relate to the difference in localised magnetic anomalies compared with the general magnetic background. Each data point is geographically referenced using an on-board Trimble RTK survey grade GPS system. Readings were taken at 0.125m centres along traverses 1.0m apart. Readings relate to the difference in localised magnetic anomalies compared with the general magnetic background. The magnetometer survey has not recorded any magnetic responses that could be interpreted as being of definite archaeological interest. A number of trends of uncertain origin have been detected in the survey which are probably due to agricultural processes. Amorphous responses and an overall increase in the background magnetic levels have been caused by variations in the underlying geology or weathering of the natural bedrock. Two strong ferrous anomalies are a result of pylons.
Thomas Cockcroft (Mon,) studied this question.