Fieldwalking
In archaeology, survey or field survey is a type of field research by which archaeologists (often landscape archaeologists) search for archaeological sites and collect information about the location, distribution and organization of past human cultures across a large area (e.g. typically in excess of one hectare, and often in excess of many km2). Archaeologists conduct surveys to search for particular archaeological sites or kinds of sites, to detect patterns in the distribution of material culture over regions, to make generalizations or test hypotheses about past cultures, and to assess the risks that development projects will have adverse impacts on archaeological heritage. The surveys may be: (a) intrusive or non-intrusive, depending on the needs of the survey team (and the risk of destroying archaeological evidence if intrusive methods are used) and; (b) extensive or intensive, depending on the types of research questions being asked of the landscape in question. Surveys can be a practical way to decide whether or not to carry out an excavation (as a way of recording the basic details of a possible site), but may also be ends in themselves, as they produce important information about past human activities in a regional context.
A common role of a field survey is in assessment of the potential archaeological significance of places where development is proposed. This is usually connected to construction work and road building. The assessment determines whether the area of development impact is likely to contain significant archaeological resources and makes recommendations as to whether the archaeological remains can be avoided or an excavation is necessary before development work can commence.
Archaeologists use a variety of tools when carrying out surveys, including GIS, GPS, remote sensing, geophysical survey and aerial photography.
Survey work may be undertaken in response to a specific threat (such as proposed or pending development project) to an area of known or unknown archaeological interest or as part of a program addressing specific research topics. In either case actual fieldwork is most likely to be preceded by a phase of desktop research (reviewing existing data in the form of maps, formal and informal written records, photographs and drawings) or in the modern age internet research using search engines, ancestry and birth or property records online. Consideration should be given to the nature of the landscape (vegetation coverage, existing settlement or industry, soil depth, climate) before a range of techniques is selected to be applied within an appropriate overarching method.
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