Conclusions

Abstract

The correlation of structures and their assignment to structure sets is an integral part of a process that embodies a series of closely interrelated steps involving continual modification and refinement of observations made in the field. These entail repeated checking of the significance of characteristic features, as well as comparison of individual structures and their overprinting relationships with structures belonging to other sets. As this nearly always involves comparison of structures between separate exposures it is important to have as much information about the structures as possible. This means that every aspect of the structure, attitude and style, as well as overprinting relationships, needs to be taken into consideration. The ease with which correlation between structures can be effected depends on the number of structural features they possess and how easily recognizable they are. If there are several and if they are distinctive, then there is less likelihood of ambiguity. A structure with particular distinctive characteristics which is widely developed is suitable for use as a datum or reference structure - what has been called a ‘key structure’ here -(see section 6.3).