High resolution magnetometry survey UK
SafeLane Global conducted a high resolution magnetometry survey to identity potential items of ordnance at a former RAF base in Gloucestershire.
The magnetometry survey findings
A bi-product of the survey was a detail magnetic map of archaeology of the local area.
The client’s aim was to change the use of a former airbase from agricultural land to mineral extraction.
SafeLane Global undertook a desktop risk assessment of the site, this indicated a medium to high risk or ordnance across the site – especially in the live firing range.
A recommendation for a non-intrusive magnetics survey to identify discrete ferrous objects was made.
A total of 200ha was surveyed within a 2 week period; the survey was carried out using SafeLane Global’s propriety AGS magnetometer system, equipped with four Geometrics G822 total field magnetic sensors.
A Trimble ProXRT with Ominstar G2 correction service (accuracy of 10cm) was used to position the data.
The system was then mounted on to a trailer and towed behind an ATV to increase the production of the data.
Upon completion of the field survey the data was interpreted off site using AGSProc software from which magnetic dipoles caused by man-made ferromagnetic objects, electrical fields or variations in the geological strata can be identified and mathematically modelled. Those that model with the characteristics of discrete objects have then been identified.
The survey detected a total of 2,858 discreet magnetic anomalies with 498 of these modelling over 10kg.
The outcomes were:
Rapid and large scale collection of magnetic data with high resolution capable of detecting an item of ordnance. With the high degree of sensitivity of the AGS survey system, areas of archaeological interest have been identified.
This survey data was collected quicker than conventional archaeological survey techniques.