Guides and case studies
Practical answers about GPR and utility surveys, and examples of what our surveys have found.
Practical guides
How much does a GPR survey cost?The factors that set the price of a GPR survey, what a quote should include, and how to get an accurate price for your site.What is underground surveying?How underground surveys map utilities, obstructions and voids before construction, and why GPR is the main tool for the job.What are pile caps and how to locate themWhat pile caps do, how they are built, why GPR finds them only some of the time, and better ways to locate them.What are sinkholes?The types and causes of sinkholes, where they occur in the UK, the warning signs, and how GPR maps them.
Case studies
The secret tunnel in Liverpool that turned out to be a sewerWe used GPR to search for a rumoured prisoner tunnel between two Liverpool landmarks. The survey found a sewer instead.Buckland Rings Iron Age hillfort: GPR compared with magnetometry and EMOur GPR survey of Buckland Rings, a scheduled Iron Age hillfort, found possible roundhouses, trackways and pits that earlier geophysics had not shown.Finding hidden crypts and vaults with GPRHow GPR detects crypts and vaults beneath church floors, and how we mapped a hidden vault found during lift shaft works.GPR at Bournemouth University's excavation near Corfe CastleOur GPR survey beside Bournemouth University's excavation near Corfe Castle found ditches, pits and a possible man-made dock.Iso 3D tomographic projection of gravesHow we turn GPR array data into a 3D view of grave positions and depths, with an example from a completed survey.Layers, kilns and buried walls: GPR tested against an open trenchTest surveys beside live excavations let us check GPR against exposed layers and use tomography and 3D iso projection to pick out possible buildings and kilns.