PALEONTOLOGICAL "BIG GAME HUNTING:" CAPTURING THE ACTIVITIES OF ANCIENT ORGANISMS WITH A CAMERA: PHOTOGRAMMETRIC ICHNOLOGY IN NORTH AMERICA, EUROPE, ASIA, AND AFRICA

As cameras are currently standard pieces of field equipment, close-range photogrammetry (CRP) is one of the easiest and most cost-effect digital data collection techniques. Vertebrate trace fossils reflect the complex interrelationship between an animal’s activities and the substrate. Digital ichnological and spatial data capture the incredible wealth of information provided at tracksites and provide the basis for photogrammetric ichnology. CRP can assist in the proper documentation, preservation, and assessment of ichnological resources, as stereo images have the quality, reliability, and authenticity necessary for scientific use. Three-dimensional image datasets created from stereoscopic digital photography provide permanent digital records of fossil tracks, including the creation of digital type specimens. CRP is a non-invasive, objective recording and analysis method, which provides a visual, quantifiable baseline to evaluate track-bearing surfaces. It has been especially useful in remote locations of Great Britain, Korea, Tanzania, and United States. Not only do CRP datasets support accurate visualization of the fossils, they can also be used to create high resolution, solid, 3D models. As 3D terrain surfaces or point clouds created from photogrammetric documentation may contain thousands of very accurate x, y, and z coordinates, researchers can measure various ichnological dimensions at a submillimeter level. Even denser point clouds can be produced with the development of GigaPan robotic mounts, which allow for the collection of extremely high-resolution stereoscopic panoramic images. In addition to traditional ichnological measurements, unbiased, higher-level, mathematical analyses may be conducted on the 3D data. Software algorithms can automatically quantify areas of surface curvature, roughness, slope and other morphometric characteristics. Photogrammetric ichnology allows for objective morphological correlations of various ichnofaunas (e.g., dinosaur tracks in Wyoming, Utah, Scotland and England) to be made and data normalized (e.g., converting convex hyporelief forms to concave epirelief) for comparison. In addition, it is currently being used to assist in the management and interpretation of Paleozoic-Pleistocene tracksites on public lands in the West.