GIS-Based Image Enhancement of Conductivity and Magnetic Susceptibility Data from Ureturituri Pa and Fort Resolution, New Zealand

• Published in: American Antiquity
• Main Authors: Ladefoged, Thegn N., McLachlan, Sheena M., Ross, Sarah C. L., Sheppard, Peter J., Sutton, Douglas G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1995
• Subjects: Museology; Archeology; Arts and Humanities (miscellaneous); History; Fort Resolution; New Zealand
• Online Access: http://dx.doi.org/10.2307/282260; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0002731600057589

Two geographic information system (GIS) techniques for displaying, analyzing, and interpreting geophysical data were recently applied at two archaeological sites in northern New Zealand; a pre-European Maori pa (fortification), and a late nineteenth-century European fortification. A GIS was used to stretch and filter the conductivity data from the pa to accentuate subtle contrasts and clearly delineate boundaries between areas with contrasting conductivity readings. Magnetic susceptibility data and two different bands of conductivity data from the historic fort were used as input for a GIS-based unsupervised classification. The classification delineated five spatial entities, several of which corresponded to known archaeological features. The interpretability of the geophysical data in relation to conventional visual analysis of conductivity contour maps was enhanced through the use of the GIS procedures outlined.