QUANTIFYING MORPHOMETRY THROUGH 3-D MODELS PRODUCED BY UAV PHOTOGRAMMETRY OF VOLCANIC CRATERS AND COLLAPSE FEATURES IN DIAMOND CRATERS, OREGON AND IMPLICATIONS TO MARTIAN CRATER FIELDS

The Diamond Craters of Oregon provide a unique location containing craters of volcanic and collapse origins, which can serve as a terrestrial analog to the surface of Mars. 3-D models produced from Unmanned Aerial Vehicle (UAV) photogrammetry in Diamond Craters allowed for morphometric quantification of the craters. Morphometric perimeters include major and minor axis, aspect ratio (AR), circularity, depth of crater from summit, summit peak height, and slope angles. Major axis values range from 7-1022 m, and minor axis range from 3 -393 m. Areas range from as little as 52 to 384,708 m². The smallest crater imaged has a perimeter of just over 27 m while the largest 2,667 m. Craters ranged from long and narrow (min AR 0.1) to circular (max AR 0.9). Crater shape was correlated with crater formation mechanisms, especially craters related to phreatomagmatic eruptions. The use of UAVs for geologic work to date, mostly involves photo reconstructions with little to no quantitative work. Since UAVs can capture large areas quickly with overlapping high-resolution photography, geologists are now capable of producing 3-D models for quantifying landforms with increased precision in less time and with lower cost over previous methods, e.g. satellite imagery or topographic profiling. The UAV derived terrestrial morphometry will be invaluable for quantitative comparison of crater regions currently only accessible remotely, e.g. the Martian surface.