Surface Architecture Scanning of Archaeological Sites with Ground Based Lidar in Southern Peru

Ground based LiDAR scanning provides an innovative technique for investigating partially buried architectural structures in Southern Peru. In this paper, we evaluate the potential of ground-based LiDAR for elucidating the nature of archaeological structures with vestiges of architecture remaining on the surface. Microtopographic mapping provides evidence for subsurface architecture as well as documentation of elements of preserved standing constructions. We evaluate the potential for LiDAR to provide data on submerged structures as a complement to geophysical and excavation techniques. We also examine LiDAR’s role in documenting erosional processes and in enhancing monitoring of destruction to monumental archaeological sites. Two sites are examined as case studies: the Inka (1450-1532 CE) administrative center of Sabaya and the Wari (600-1000 CE) administrative center at Cerro Baúl

Evaluating airborne laser data on steeply sloping terrain

Accuracy of Airborne Laser Terrain Mapping (ALTM) elevations is not well known on steeply sloping terrain. A unique method was used whereby, the planimetric location of ALTM ground strikes were located in the field and reference elevations measured at these points. Survey-grade Global Navigation Satellite System (GNSS) and rigorous techniques accurately established vertical heights to 0.010 meters, Root Mean Squared Error (RMSE). Sampled slopes range from 0.5 degrees to 50.6 degrees. A positive quadratic relationship exists between slope and vertical error. Error is negligible on slopes less than twenty degrees. Incidence angle, footprint size, and elevation spread from the upper reach of the footprint to the lower reach for each laser strike were also determined. An increase in each results in an increase in ALTM elevation imprecision. Elevation spread within the footprint and horizontal error could account for high percentages of vertical error on steeper slopes