LIDAR/PHOTOREALISTIC GEOSPATIAL REFERENCE SYSTEM FOR AN INVESTIGATION OF THE BIOCOMPLEXITY OF EXTREME ENVIRONMENTS, MICKEY HOT SPRINGS, ALVORD DESERT, SOUTHEASTERN OREGON

Study of microbial and environmental interdependence within Mickey Hot Springs, located in the Alvord Desert of southeastern Oregon, requires a high-resolution geospatial network to characterize and correlate variations in microbial diversity, the physical and chemical conditions of hot spring vents, and structural control of the hydrogeologic system. Existing topographic maps, digital orthophotoquads, and digital elevation models do not provide adequate resolution and a spatial framework was developed using ground-based LIDAR coupled with photographic imaging of the hot spring surface morphology. We employed a Riegl Z360 reflectorless laser scanner and acquired over 50 million sub-centimeter accuracy XYZ points along with intensities and RGB. Spatial control was global, provided by dual frequency Leica GPS receivers linked by FM radio. Surface morphology alone did not provide sufficient control on the nature of the substratum, and the area was digitally imaged using a Canon D60 digital camera (3000x2000 pixels per image). The digital photographs were transformed to conform to the high-resolution DEM using a Helmert minimization algorithm and tied to the surface morphology by GPS surveyed control points. This technology provides the means to capture detailed field relations in 3D for spatial registration, surface characterization, and archival preservation of critical field relations. Possibly more importantly, photorealistic imaging allows subsequent analysis and interpretation of field relations in the visualization laboratory without loss of spatial resolution.