TerraDat
Unit 1, Link Trade Park, , Penarth Road,, United Kingdom

TerraDat Geophysics was established in 1992 to address the need for increased awareness of the subsurface in the context of land use and environmental legislation. About that time many of the geophysical techniques that had been standard in deeper, large scale mineral-type surveys took advantage of technological developments and became smaller, more portable and offered higher resolution of the buried physical targets that were being mapped.

Since our incorporation, we have worked hard to establish to the adoption of geophysical mapping technology in a wide range of industries ranging from landfill, nuclear site characterisation, contaminated land mapping, coastal geotechnics and civil engineering projects.

TerraDat aims to provide the highest quality non-destructive geophysical surveys to a broad cross section of industries using a multi-disciplinary approach. We undertake to continually invest in our staff and technical facilities so we can combine this with our extensive global experience and pass this on to our customers as a service of the highest quality.

In recognition that geophysics is a relatively new and constantly evolving science, we will maintain a commitment to educating and training new graduates and the industy through technical contributions to research projects and publications.

Download a PDF of our company brochure: a 20 page booklet outlining the benefits of using geophysics, followed by several real life case studies and backgrounds to all the main geophysical methods.

Geomatics:

A secondary capability running alongside our geophysical expertise is 3D measurement of surface targets. This aspect of our work came about through a combination of our long term relationship as a customer of survey equipment manufacturer Topcon, and the need to produce accurate maps on which to plot our geophysical survey results. We are now an authorised dealer for Topcon in terms of their high end imaging technology including Terrestrial Laser Scanning and Photogrammetry.

Services

Geophysics is a modern science routinely applied to ground exploration. A range of survey tools are available for mapping/profiling subsurface targets such as mineral bodies, engineering rockhead, shallow archaeology, environmental contamination through to unexploded ordnance.

Why use Geophysics?
Geophysical surveys should be a routine part of most ground investigations for civil engineering projects and mineral exploration. The use of geophysics often represents the only way of achieving total ground coverage to ensure targets are reliably identified and imaged prior to invasive work. The points below outline the clear advantages of using our services

Low Cost – Geophysical surveys offer remarkable value for money when compared to more conventional site investigation techniques alone. The value of the information acquired combined with the reduced cost from an optimally designed follow-up invasive investigation easily exceeds the original outlay – not to mention the reduced legal implications of failing to use all the common tools for site investigation available and missing the target as a result.

Rapid Coverage – Up to 2-6 hectares of land can be typically surveyed in one day on an engineering scale project or a much greater area it the target is minerals. If surveys are carried out along profiles, then up to 5km can be acquired depending on the method. Sometimes it is possible to deliver draft results of anomaly locations whilst on site (subject to final data processing and analysis). All our surveys are tied in to National Grid coordinates or local site grid making relocation of anomalies simple and accurate.

No Exposure to Buried Hazards – Because geophysics is non-invasive, neither operators nor other people on site are exposed to hazardous material.

Minimal/ No Surface Disturbance – Since little or no ground penetration is required geophysical surveys can be carried out in urban areas, highways or landscaped environments without disturbing the surface.

Easy to Comprehend – We take special care to present our findings in a format that can be easily understood and integrated with other site datasets by non-geophysical specialists. The results are presented as scale engineering sections or annotated plans that clearly define the features of interest for the Client.

Integrated Capability – We own all of our survey equipment, which enables selection of the most suitable method to use on site without compromise. Our survey teams can respond efficiently to unforeseen ground conditions and optimise survey design while on site.

Low Risk – We understand that some customers may be unfamiliar with geophysics or the recent advances brought about by modern instrumentation.

Consequently, as standard we provide free consultation for the Client from the initial design stage right through to post report discussion. Our objective is to ensure the job brief is met efficiently by optimal survey design within the site investigation budget. Our approach has proven very popular over the years with the main body of our work coming in the form of repeat custom.

TerraDat uses a suite of several different geophysical survey methods to map the subsurface. We own all of the specialist survey instrumentation needed to carry out geophysical surveys and having a complete capability in-house means that we routinely combine methods to measure anomalies from different subsurface properties. This approach significantly improves the changes of success of fulfilling the key survey objectives.

Our choice of geophysical survey method is made by making an appraisal of the physical properties of the target to identify any potential contrast with the subsurface materials. Appropriate survey techniques are then chosen to best exploit the contrast in physical properties and reveal the target’s location, either  in plan or cross-section.

The suite of geophysical survey techniques that TerraDat routinely employs includes:

• Microgravity: target density contrasts to identify voids, geological features or mineral bodies
• Seismic reflection and refraction: P and S-wave velocity contrasts to profile bedrock, overburden layers and rock strength
• Borehole Seismics: downhole and crosshole seismic surveys to quantify subsurface engineering properties
• Electromagnetics: map subsurface geo-electrical changes to identify anomalies due to overburden variations, boundaries, plumes etc.
• Electrical Resistivity: profile geo-electrical properties to map top of bedrock, overburden changes, buried channels etc.
• Ground Penetrating Radar (GPR): 2D and 3D mapping of the subsurface to characterise geological and structural features.
• Magnetics: for mapping buried ferrous targets such as drums, tanks or UXO (unexploded ordnance)
• Induced Polarisation surveys (IP): locating and characterising mineral deposits
• Radiometric surveys: measure naturally occurring gamma radiation
• Methane Gas surveys: soil vapour gas surveys to map methane gas and detect hydrocarbons
• Utility Survey Methods: a suite of radiodetection methods to locate shallow services and utilities