APPLICATION OF MULTISPECTRAL DRONE (SUAS) PHOTOGRAMMETRY TO IMPROVE DINOSAURIAN ICHNOFOSSIL TRACKWAY IDENTIFICATION IN THE CACTUS PARK AREA, WESTERN COLORADO USA

The advent of drone (small unmanned aerial systems; sUAS) photogrammetry as an accessible tool for geologic research has changed the way that ichnologists may record and analyze data from dinosaurian trackways. Very-high-resolution—sub-cm scale—digital elevation models (DEMs) created from structure-from-motion (SfM) photogrammetry allow for the creation of extremely accurate site maps and can reveal traces and biometric or biomechanical data that would have otherwise gone unrecognized. There is an abundance of track sites on the Colorado Plateau, and while some more unique or recently discovered track sites have been analyzed via 3D modeling, many were only described during the “dinosaur renaissance” of the 1970s and 1980s without the aid of modern technology. The recording of sites via drone photogrammetry is non-destructive, non-invasive, and allows for more detailed research to be conducted in the future, even by researchers who cannot easily go out into the field. In addition to standard SfM photogrammetry in building 3D models of dinosaurian ichnofossil trackways, multispectral drone imagery now provides an additional orthoimagery tool that can highlight features not available by eye, through high-resolution RGB imagery, or in very-high-resolution DEMs. This study provides a systematic analysis of ground-based photogrammetry/SfM, drone based RGB photogrammetry/SfM, and multispectral photogrammetry/SfM. Results indicate that specific multispectral band-mixing “recipes” provide additional information not available through other techniques. Data are provided from a small site of dinosaurian trackways in the Cactus Park area of Western Colorado USA. Our objective is to present methodology that may reveal new details of track sites, up to and including entirely new trackways that are overlooked or uncertain in field observations.