Measured Survey

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Measured Survey involves measuring distances and angles to produce 3D data and/or 2D plans and drawings of archaeological sites and structures. Wessex Archaeology typically use survey instruments for such work, for example Global Navigation Satellite Systems (GNSS) and/or Total Station Theodolites (TST).
 
The TST uses laser beams and an angle measuring device combined with a data logger all in one instrument. TST work is a form of direct data capture whereby the surveyor uses the instrument to measure specific points and lines on the subject. We use these to record buildings, structures and architectural details and on archaeological excavation sites to record precise locations of artefacts or skeletal remains.

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When working on buildings or structures, our surveyors typically use such instruments in conjunction with tablet computers to allow them to build a 3D wireframe model of the subject in real-time in the field, a highly efficient process which allows them to see their results as they go and  ensures high quality data is captured. From this 3D CAD drawing, we can then produce elevation drawings and interpretive figures such as phase plans showing the development of the building or structure through time.

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The GNSS uses satellites to calculate an exact position on the earth’s surface to within a centimetre, another form of direct data capture. GNSS covers a family of systems including GPS operated by the United States, GLONASS operated by Russia, Galileo operated by Europe and Compass operated by China. These instruments allow us to rapidly undertake topographic survey of earthworks and landscapes and are also used to locate TST surveys within the British National Grid coordinate system as used by the Ordnance Survey.
 
Both GNSS and TST are used for monitoring of archaeological assets, to measure any change over a period of time. This includes activities such as monitoring erosion over earthworks and monuments or deformation in a structure.

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Guidance for metric survey projects is provided by the Metric Survey team at English Heritage and all our work is undertaken to their standards. Wessex Archaeology are also members of the Survey Association, a professional body for organisations undertaking survey work.
 
Contact us on 01722 326867 or email p.baggaley@wessexarch.co.uk for further information.