Archaeological surveying with airborne LiDAR and UAV photogrammetry: A comparative analysis at Cahokia Mounds

Remote sensing technologies are becoming indispensable for archaeological fieldwork, helping archaeologists be more efficient and focused in their excavations. Assessing technological feasibility and capability is therefore an essential skill for archaeologists. This research compares digital elevation models from publicly available air-plane Light Detection and Ranging (LiDAR) data and unpiloted aerial vehicle (UAV or drone) images to analyze the quality, costs, and benefits of both. Data were collected at the Grand Plaza, which served as the ceremonial center for the civilization at Cahokia Mounds, Illinois, USA, a UNESCO World Heritage Site. GPS elevation data and the Local Binary Pattern (LBP) texture operator were applied to evaluate topographical fidelity in the DEM imagery. We find that photogrammetry is a suitable replacement for LiDAR in specific areas, namely areas with low-lying vegetation. Thus, archaeologists have multiple surveying options and must carefully weigh the technologies available to them based on time and resource constraints.