Meteorite impact craters as natural "probes" and "gauges" on planetary surfaces

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Impact cratering is the most ubiquitous geologic process acting on solid planetary surfaces throughout the solar system and, thereby, played a significant role in the early formation, modification and in some cases the aqueous alteration of planetary crusts. Mounting evidence supports that impact cratering has not only physically modified the rocky surfaces of Earth and Mars, but may have also played a significant role in the evolution of early life and the concentration of mineral resources via the hydrothermal activity (i.e., heat-driven circulation of fluids). Impact craters are relatively consistent in morphology making them one of the most easily recognized features on planetary surfaces. Thereby, they are also useful as “probes” and “gauges” of the target properties, and geologic processes that modify planetary surfaces, respectively. Craters excavate, uplift and expose subsurface rocks that may not otherwise be exposed by other processes, and in some cases provide the only bedrock samples of the deep subsurface. Spectral remote sensing of theses features is often employed to identify these subsurface rocks on planetary bodies. However, there are various crater-related effects within these features that need to be better understood, in order to fully understand their effects on the rocks. Pristine crater morphology and morphometry (e.g., crater depth) can be used as a standard to understand target material properties and the effects and rates of subsequent modifying geologic processes. In addition, pristine craters offer us a glimpse of the relatively unmodified primary crater deposits, providing insights into the impact cratering process itself, and potentially paleo-environments on planetary bodies with atmospheres and target volatiles (e.g., water). The long-term goals of my research program are to, 1) improve our understanding of the impact cratering process as a geologic process, and 2) learn about the geological history of upper crust and surface of Mars through remote sensing studies of its most ubiquitous landform – impact craters. This program aims to achieve these goals via three testable hypotheses, each of which are divided into four objectives involving the analysis and interpretation of orbital spectral, visible, thermophysical and elevation data sets of the Martian surface. Although the emphasis is not specifically terrestrial-based, the processing, visualization, analysis and interpretation of these data sets are similar to those utilized by exploration geology, geophysics, environmental remote sensing, and even employed for the purposes of national defense. As such, Highly Qualified Personnel (HQP) involved in this research program will learn techniques that are directly applicable to these fields.