eTheses Repository - University of Birmingham

The problems start with the paper maps. Often they are very detailed and decisions relating to
which information is needed for digitization always have to be made before any work can
progress. The implications of this are important: paper maps are simply a representation of
the “real” world perceived a certain way at a particular moment of time. They have been
compiled as a result of decisions made by the cartographer as to how physical features should
be represented, and indeed which ones should be included, often dictated and informed by the
authorities who commission the maps. Nowadays there are certain standards to which the
cartographer must adhere depending on the mapping authority, and the scale of the map
largely dictates whether for example a city is characterized by a dot or by many polygons
representing individual features within the city. Maps reduce the landscape in which we live
to a version of reality that purports to be accurate and true.
Digitising the paper map is another step away from the physical landscape, where further
decisions need to be made that relate to which features should be used within a GIS, and how
accurate they are required to be, depending on the purpose for which the particular project is
being designed. In addition, data from maps may not show all the possibilities required in
order to answer questions the GIS will be asked. For example, some topographical maps may
not indicate whether a water source is seasonal or perennial, and certainly will not say
anything directly about the quality of the water. Although geological maps may indicate the
possibility of mineral inclusions in water, this depends on many other factors such as the flow
of water, and whether it is ground water in the form of a river or lake or a deeper source
accessed via a spring or well. Although there is very little that can be done about this, it is
important to be aware of the fact that map information is and can be nothing else other than
subjective and as such needs to be used critically. This is especially pertinent for the purposes
of GIS in archaeology where the act of digitising and then using the results to say things about
that landscape in the past, creates a version of a version of a version. In addition, where it is
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