What lies beneath? The benefits of geophysical survey for quantifying and managing archaeological risk on your development

07 Apr 21

Archaeological evaluation is often required in support of planning applications, or secured by a planning condition, as the first step in determining whether further archaeological mitigation may be required. Engaging geophysical survey for your archaeological requirements is a powerful non-destructive tool in defining this evaluation scope.

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If someone mentions the words geophysical survey in passing conversation, it is likely to elicit one of two reactions; the first being a glazed expression serving as facial code for ‘what is a geophysical survey?’. The second, and slightly more informed, might bring to mind images of cold looking students in woolly jumpers, walking across a muddy field strapped to large, heavy metal devices. Neither reaction is without foundation.

Fortunately, however, physical surveying techniques have come a long way since the early days of Time Team, and can be an incredibly efficient tool for determining what is in the ground, help to illustrate potential risks to a development prior to a planning application, or even just a map of sorts prior to site purchase.

Geophysical survey is an umbrella term for a number of different physical survey techniques including magnetometry, ground penetrating radar (GPR), earth resistance, EM conductivity, earth resistivity tomography, and magnetic susceptibility. These techniques are wide ranging and used across multiple industries, including archaeology, geology, mineral and energy exploration, oceanography, engineering, and for the detection of UXO. The systematic collection and analysis of geophysical signals allows anomalies to be plotted, enabling the non-destructive mapping of subsurface archaeological features prior to physical evaluation.

Why does this matter? Archaeological evaluation is a phase of initial field testing that aims to establish the nature, extent, and significance of any archaeological remains present on a site. Archaeological evaluation is often required in support of planning applications, or secured by a planning condition, as the first step in determining whether further archaeological mitigation may be required. Engaging geophysical survey for your archaeological requirements is a powerful, non-destructive tool in defining this evaluation scope. When it is a component of a well-integrated evaluation design, combined with detailed desk-based research, it can be used to map potential areas of archaeological sensitivity and is useful in understanding the nature of any developmental constraints at an early enough stage to avoid impact on the developing design or construction programme, saving huge amount of time – which not surprisingly, equally money on a project.. Additionally, it can be used positively when you need to progress to trial trenching stage in negotiating and reducing the scope of works and associated cost based on a tangible, valid data source.

At Iceni Projects, we will work with you and industry-leading geophysical specialists to tailor a bespoke survey programme for your archaeological feasibility and fieldwork requirements, ensuring cost-effective outcomes for your archaeological evaluation requirements. And if this is all still Greek to you, don’t worry; we’re here to help, especially as its most likely Anglo-Saxon.

If you would like to know more about the value of geophysical survey, please feel free to contact the Iceni Projects Archaeology Team.

Sarah Ricketts Archaeologist,Archaeology