Mineralogical Diversity and Crustal Composition of Selected Lunar Regions Based on M³ Hyperspectral Analysis: Implications for ISRU and Future Exploration

Characterizing lunar surface mineralogy is essential for understanding crustal evolution, magma ocean differentiation, impact excavation processes, and identifying In-Situ Resource Utilization (ISRU) targets for future exploration. This study determines the mineralogical composition and crustal stratigraphy across four geologically distinct lunar terrains using Moon Mineralogy Mapper (M³) hyperspectral data: the Aristarchus plateau (volcanically complex), Dionysius crater (a pristine impact structure), the Malapert region (ancient highlands of the South Pole), and Leibnitz R (primordial anorthositic crust).

Level-2 M³ hyperspectral cubes (430-3000 nm, 140 m/pixel) [1] were processed through systematic workflows: destriping, photometric normalization, Minimum Noise Fraction (MNF) transform, Pixel Purity Index (PPI) endmember extraction, continuum removal, and Spectral Angle Mapper (SAM) classification. Spectral signatures were validated against RELAB laboratory spectra resampled to M³ resolution. Key mineral phases identified include anorthite, low-calcium pyroxene (LCP), high-calcium pyroxene (HCP), olivine, spinel-bearing assemblages, and ilmenite.

Aristarchus exhibits the highest mineralogical diversity [2], with anorthositic highland material, HCP- and LCP-bearing mafic units, and localized olivine signatures. Anorthosite absorption features (1.25 µm band depth) dominate the crater floor, pyroxene signatures characterize the ejecta blanket, and olivine (1 µm band depth) appears along crater rims. This heterogeneity reflects volcanic emplacement and deep impact excavation, offering diverse oxygen-rich and iron-bearing ISRU targets.

Dionysius (Mare Tranquillitatis) reveals systematic radial mineralogical zonation from HCP-dominated rim materials to LCP-enriched central exposures, indicating excavation through compositionally stratified crust. This vertical gradient constrains upper crustal HCP overlying lower crustal LCP layers [3,4], consistent with magma ocean crystallization models. Olivine and ilmenite detections suggest penetration to mafic lithologies, constraining crust-mantle differentiation.

Malapert (South Pole) is predominantly anorthositic, with isolated spinel-bearing outcrops (5% band depth at 2 µm) associated with uplifted crustal blocks. These exposures constrain deep crustal composition and early magma ocean differentiation. The area's abundant anorthosite and its location near permanently shadowed regions make it a key site for oxygen extraction and the establishment of polar exploration facilities.

Leibnitz R (far side) displays spectrally pure anorthositic composition, representing primordial crust formed during lunar magma ocean plagioclase flotation. Its compositional homogeneity provides a reference for early lunar differentiation and high-purity feedstock for ISRU oxygen production.

This study integrates hyperspectral mineralogy with surface morphology to constrain crustal architecture and geological evolution across diverse lunar environments. The methodology establishes a replicable framework for hyperspectral analysis applicable to future mission planning, linking fundamental crustal processes to ISRU resource assessment and advancing sustainable lunar exploration strategies.

References: [1] Green et al. (2011) JGR: Planets, 10.1029/2011JE003797; [2] Chevrel et al. (2009) Icarus, 10.1016/j.icarus.2008.08.005; [3] Moriarty & Pieters (2018) JGR, 10.1002/2017JE005364; [4] Wieczorek et al. (2013) Science, 10.1126/science.1231530

Acknowledgement: EU HORIZON-MSCA-2023-SE-01, Grant 101183089