Readers of our blog will know that in August last year, Dr Richard Bates of St. Andrews University carried out an electromagnetic conductivity survey for us on the lawn of Priory House, Christchurch. We have recently published the report summarising the survey and its results. Since the Priory House grounds which we surveyed are within the boundaries of the Scheduled Ancient Monument which protects the remains around the Priory Church of the Augustinian Priory of which the church formed a part, our survey was conducted under the conditions of a Section 42 licence granted to us by English Heritage. The survey was conducted with the permission of, and at the request of, the trustee of the Priory House Charity.
The purpose of the survey was to see whether we could discover evidence of the demolished remains of the Priory which are believed to lie under the lawn of Priory House (some remains of ancient walls are still upstanding at the edges of the lawn, and elsewhere on the Priory site). Dr Bates used an electromagnetic conductivity meter which provides readings of conductivity and a measure of the relative magnetic susceptibility of the soil, and is configured to provide readings from three exploration depths simultaneously. The instrument is interfaced with differential GPS kit which tags each set of readings with centimetre-accuracy positioning. This type of instrument is not commonly used currently in archaeological geophysical surveys and this provided a great opportunity to assess the effectiveness of the technique.