2D Mapping of Peridotite Analogs as Target Minerals for Martian Missions using Planetary Exploration Technologies

Abstract

Peridotites represent ultramafic lithologies characterized by wide mineralogical and chemical variability, making them ideal natural analogs for testing and validating analytical techniques relevant to planetary exploration. In this work, a peridotite sample from the Ronda Massif (Málaga, Spain) was characterized, demonstrating a practical methodology for distinguishing geochemically distinct regions within complex lithologies [1]. The sample was analyzed using a multi-instrumental approach combining LIBS, micro-energy dispersive X-ray fluorescence (µ-EDXRF), and Raman spectroscopy, all of which are integrated into the Perseverance rover payload. LIBS and µ-EDXRF were used to assess elemental composition and spatial distribution across the sample, and the results of both techniques for major elements showed good agreement in spatial trends. However, LIBS was also able to identify minor elements such as C, Sr, and Na, which are of particular interest in mineralogical studies due to their relevance in mineral structure, alteration processes, and geochemical signatures. Raman spectroscopy confirmed the presence of mineral phases such as olivine, pyroxenes, and chromiferous spinels in specific regions. Elemental LIBS ratios such as Mg# (Mg/(Mg+Fe)) and Cr# (Cr/(Cr+Al)) supported the identification of compositional variations related to mineral phases [2]. Spectral LIBS data were processed using k-means clustering to segment geochemical zones and detect spatial trends. This integrated spectroscopic and statistical approach enables a better interpretation of ultramafic rock complexity and provides an efficient framework for planetary exploration under mission constraints.