EMIT for lithological mapping

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Grant Title: EMIT for Lithologic Mapping, Mineral Exploration, and Tectonic Investigations in Arid Lands Funding Agency: NASA Grant Number: 80NSSC24K0863 Period :2024 - 2027 Abstract: We are evaluating the lithologic mapping capabilities of EMIT, their application for identifying mineralization in arid and hyperarid crystalline terrains, and their potential contribution to our understanding of the accretionary and post-accretionary history of areas under investigation. We selected as our test sites, the once contiguous Eastern Desert of Egypt in the Nubian Shield and the Midyan Region in the Arabian Shield prior to the Red Sea opening. They were selected as test sites for the following reasons: (1) vegetation and cloud coverage is minimal to absent, (2) the test sites host the overwhelming majority of the lithologies of the Arabian Nubian Shield (ANS; ~2.5 M km2) and thus, the developed EMIT-based mapping capabilities could be readily applied elsewhere across the ANS, (3) we have already field checked, sampled, and analyzed many of those units within the test sites for their mineralogic, petrographic, and spectral characteristics, and (4) the test sites encompass multiple gold mineralization sites. We will investigate the extent to which EMIT data can be used to accomplish the following objectives: (1) improve existing geologic maps and Landsat TM-based lithologic maps, (2) use the generated regional maps to enhance our understanding of the accretionary history of the ANS, (3) correlate the lithologies and structures along the Red Sea coastlines and further investigate the validity of pre-Red Sea reconstructions including ours (pole: lat. 34.6°N, long. 18.l°E; rotation amount: 6.7°) and constrain the post-accretionary history of the ANS, (4) develop and test an exploration model that integrates observations from EMIT hyperspectral data with regional- and small-scale tectonic and geological controls to identify existing and previously unrecognized gold mineralization locations, and (5) share and distribute the project’s data and findings with the scientific community. The objectives will be accomplished by applying an approach that integrates observations from EMIT hyperspectral data (e.g., mineral maps, supervised spectral angle mapping classifications), multispectral data (TM band ratio images), VNIR field spectrometer, petrographic (modal abundances, XRD), and geochemical data (XRF, SEM, gold assays).

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