Detailed Digital Terrain Models for Supporting the Analysis and Interpretation of Near-surface Geophysical Data

Today's near-surface geophysical acquisition approaches readily allow for combining geophysical measurements with high-resolution positioning solutions based on the global-positioning system (GPS) or self-tracking total stations (TTS). Under favourable site conditions, such surveying strategies allow for efficiently acquiring high-quality geophysical data with a positioning accuracy in the centimetre range. In addition to accurately locating geophysical measurements, such positioning data can also be used to generate a detailed digital terrain model (DTM) of the surveyed area. Here, we present two case studies where a detailed DTM supports and complements the interpretation of near-surface geophysical data. While the first case study comprises magnetic and electromagnetic induction data collected to locate buried utilities, the second case study presents a 3D ground-penetrating radar survey recorded to detect archaeologically relevant structures. In both cases, the topographic data resulting from the employed TTS-based surveying strategy are analyzed using different topographic attributes supporting the geophysical data interpretation. We conclude that, from our experience, inclusion of a detailed DTM into the geophysical data processing flow, can provide additional valuable information for data analysis and interpretation.