Terrestrial Volcanic and Impact Analogs to Small Martian Craters: Utilizing Remote Sensing and Field-based Datasets to Analyze Formational and Sediment Transport Processes

Introduction: Two terrestrial craters of different origins have been selected as field sites for this continuing work: El Elegante Crater, a maar crater in the Pinacate Volcanic Field (PVF) in northern Mexico, formed approximately 150,000 years ago from phrea-tomagmatic explosions [1-2], and Meteor Crater, an impact crater located in central Arizona, formed approximately 50,000 years ago from the impact of an iron nickel meteorite [3]. Both craters are located in arid regions and were selected due to their similarity in size, age, and climate history since formation [4]. The purpose of this work is to determine if forma-tional and sediment transport processes can be established from remote sensing datasets, with field ground-truthing, in a terrestrial setting. Methodologies to distinguish and characterize small crater formational and modification processes, which can be applied to Mars datasets, will then be developed. For this reason, terrestrial remote sensing datasets similar to those currently or soon to be available from Mars were selected for the study of these two craters [3]. Background: Small craters may represent some of the most recent geologic activity on Mars; therefore, quantifying formational and post-formation modification processes associated with these craters may have implications for understanding climate and surface evolution [4, 5]. Because maar craters are created by phreatomagmatic eruptions, the ability to recognize and distinguish them from small impacts remotely is integral in ascertaining the possible role of volatiles in Mars surface processes. Previous remote sensing work at Meteor Crater has focused on ejecta topography and transport resulting in lithologic unit mapping using linear deconvolution of thermal infrared (TIR) data at varying resolutions [6-8]. Current work expands on this analysis by using datasets over a broader spectral range and higher resolution at Meteor Crater and applies similar methodolo-gies to El Elegante Crater remote sensing datasets. At both sites, the effects of non-mineralogic TIR spectra, small scale features and lithologies, and lithologies of small percentages are considered through the analysis of higher resolution data [4]. data collection and field observations were conducted at Meteor Crater and El Elegante Crater, respectively. Equipment used included a real-time differential GPS (d-GPS), a laser range finder, a Forward Looking In-frared (FLIR) camera, and a Visible and Near Infrared