Geological Mapping of the "Bossa Nova"Target for Rare Earth Elements Exploration

GEOLOGICAL MAPPING OF THE "BOSSA NOVA" TARGET FOR RARE EARTH ELEMENTS EXPLORATION. M. J. Pereira Nunes Segundo1,2 and A. Calzada Diaz1, 1European Space Resources Innovation Centre - ESRIC (mercio-john.pereira-nunes-[email protected]), 2ERASMUS Mundus Joint Master in Planetary Geoscience – GeoPlaNet. Introduction: Hosted in phosphates, carbonates and silicates in different genetic deposits, Rare Earth Elements (REEs) are relatively abundant in the Earth's crust; however, economically viable concentrations are limited, leading to a global dependency on a few supplier countries. Whose geochemical affinity with thorium (Th) and uranium (U), both enriched in the Procellarum KREEP Terrane (PKT) [1], along with reported “enriched” samples suggests targeted exploration on the Moon may be viable. This study aims to provide a preliminary assessment of REEs potential by utilizing orbital data, delineating preliminary target areas for ISRU activities, which can be validated by future missions. Methodology: To reach a more terrestrial exploration approach, this work presents efforts in compile and interpret different lunar data sets from previous missions that allowed better resolution imagery and relatively more precise geological studies in the area. The data were processed and interpreted on QGIS 4.40.3 and Envi Classic 5.7. Results: Investigating Hyperspectral Images: Nd³⁺ exhibits characteristic absorption features at 730–750 nm and 870–890 nm. These features appear weakly across the main target and surrounding areas (Fig. 3), potentially due to low REE concentrations, regolith mixing effects, or instrument noise. Geological Mapping: We produced the most detailed geological map (1:320000; Fig.1) since Iqbal et al. (2023). The selected target area, named "Bossa Nova” (BN) by us, was shortlisted based on the highest Christensen Feature values (derived from Diviner) [4], which are indicative of more evolved lithologies often associated with REE mineralization on Earth. This area may be like “granophyre clasts” observed in the thorium-rich lunar meteorite SaU 169, containing up to 4% phosphates [5]. Conclusions: Despite the resolution may limit the detection of REE-related lithology individualization, we propose at least three sub-target areas within the BN region for further REE exploration campaigns. While preliminary spectral observations are inconclusive, the combination of Christensen Features, Th distribution, and geological context supports the potential for REE-bearing lithologies. Future missions should prioritize high-resolution imaging and sample return to evaluate these targets effectively. Figure 1. Geological Map of “Bossa Nova” Target. References: [1] Jolliff, Bradley L., et al. Bull. Am. Astronom. Soc 53 (2021): 294. [2] Jolliff, Bradley L., et al. Journal of Geophysical Research: Planets 105.E2 (2000): 4197-4216. [3]. Iqbal, Wajiha, et al. Icarus 406 (2023): 115732 [4] Xu, Luyuan, et al. Icarus 386 (2022) [5] Greenhagen, Benjamin T., et al. Science 329.5998 (2010): 1507-1509.