¹C. Lefebvre, ²A. Catalá-Espí, ¹P. Sobron, ¹A. Koujelev, ¹R. Léveillé
¹Space Science and Technology, Canadian Space Agency, 6767, route de l׳aéroport, Saint-Hubert, Canada J3Y 8Y9
²Unidad Asociada UVa-CSIC, Avd. Francisco Vallés, Parque Tecnológico de Boecillo, E-47151 Boecillo, Valladolid, Spain

We demonstrate that Laser-Induced Breakdown Spectroscopy (LIBS) is capable of identifying the presence of natural rock coatings, and we define LIBS signatures of complex multi-layered coatings. This is illustrated by detailed LIBS analysis, in Mars-simulated conditions, of a rock collected in the Svalbard Islands, and which is analogous to some altered Martian rocks. The sample is a basaltic rock with sub-mm Ca–Mg–Fe–Si rich mineral coatings. LIBS elemental analysis of several distinct regions on the surface of the rock demonstrates the variability of chemical compositions of the various coatings, which is confirmed by complementary scanning electron microscope (SEM) analysis. Furthermore, the LIBS analysis as a function of the depth at different locations shows chemical variability, indicative of penetration through thin coatings of varying composition. Fine-scale, three-dimensional LIBS analysis is of interest for identifying and characterizing coatings on martian rocks, likely originating from aqueous processes, providing a rapid chemical composition as a function of the layers and further understanding of the formation of the deposits and on planetary evolution.

Reference
Lefebvre C, Catalá-Espí A, Sobron P, Koujelev A, Léveillé R (2016) Depth-resolved chemical mapping of rock coatings using Laser-Induced Breakdown Spectroscopy: Implications for geochemical investigations on Mars. Planetary and Space Science (in Press)
Link to Article [doi:10.1016/j.pss.2016.04.003]
Copyright Elsevier

¹G. Bilalbegović
¹Department of Physics, Faculty of Science, University of Zagreb, Bijenička 32, 10000 Zagreb, Croatia

Cement mineral tobermorite was formed in hydrothermal experiments on alternation of calcium-aluminum-rich inclusions (CAIs) in carbonaceous chondrite meteorites. Unidentified bands at 14 μm were measured for CAIs and the matrix of the Allende meteorite sample, as well as for Hektor and Agamemnon asteroids. The presence of cement nanoparticles may explain the feature at 14 μm

Reference
Bilalbegović G (2016) A note on cement in asteroids. Icarus (in Press)
Link to Article [doi:10.1016/j.icarus.2016.04.029]
Copyright Elsevier