RT Conference Proceedings
T1 Detection of Amorphous Carbon Enclosed in Hydrothermal Gypsum Deposits by Combined LIBS and Raman Spectroscopy: Implications for Biosignature Detection in Planetary Exploration
A1 Delgado-Pérez, Tomás
A1 García-Gómez, Laura
A1 Laserna-Vázquez, José Javier
A1 Vadillo-Pérez, José Miguel
A1 Cabalín-Robles, Luisa María
A1 Fortes-Román, Francisco Javier
A1 Rull, Fernando
A1 López-Reyes, G
A1 Sanz-Arranz, A.
A1 Calaforra, J.M.
A1 Gázquez, F.
K1 Espectroscopia - Congresos
AB The potential of laser-induced breakdown spectroscopy (LIBS) for detecting and characterizing carbonaceous materials in mineral matrices is attracting increasing interest in planetary exploration [1]. This work presents the first evidence of amorphous carbon enclosed within hydrothermal gypsum (CaSO₄·2H₂O) crystals from the Mina Rica mine (Pulpí, Almería, Spain), a recognized Martian analog site. The study integrates LIBS, Raman spectroscopy, and SEM-EDX to investigate the composition and distribution of carbon-bearing inclusions.LIBS analyses revealed C(I) (247.8 nm) atomic and CN (Δv = 0) molecular emissions in both dark inclusions and siderite-free regions, indicating the presence of carbonaceous material trapped within gypsum cleavage planes. Depth profiling confirmed the shallow distribution of carbon, while spectral ratios were used to discriminate Fe emissions from siderite. Complementary Raman spectroscopy identified the broad D (1332 cm⁻¹) and G (1602 cm⁻¹) bands that are characteristic of amorphous carbon with a low degree of graphitization. On the other hand, SEM-EDX mapping shown micron-sized, carbon-rich particles dispersed within the gypsum matrix.These findings demonstrate the capability of LIBS, especially when combined with Raman spectroscopy, to differentiate between organic and inorganic carbon sources in sulfate minerals. The results highlight the suitability of gypsum as a potential preservative host for biosignatures, reinforcing the applicability of LIBS for in situ astrobiological exploration on Mars and other planetary bodies.
YR 2026
FD 2026
LK https://hdl.handle.net/10630/45324
UL https://hdl.handle.net/10630/45324
LA eng
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 4 mar 2026