Coatings and weathering rinds at Gusev crater, Mars, investigated by depth selective Mossbauer spectroscopy

Citation

Fleischer I, Klingelhoefer G, Schröder C & Rodionov DS (2008) Coatings and weathering rinds at Gusev crater, Mars, investigated by depth selective Mossbauer spectroscopy. Hyperfine Interactions, 186 (1-3), pp. 193-198. https://doi.org/10.1007/s10751-008-9853-z

Abstract
The miniaturised Mössbauer spectrometer (MIMOS II) is part of the scientific payload of the two Mars Exploration Rovers, “Spirit” and “Opportunity” (Klingelhöfer et al., J Geophys Res 108(E12), 2003). MIMOS II can obtain 14.4 keV γ-ray spectra and 6.4 keV X-ray spectra simultaneously in backscattering geometry. Comparing 6.4 keV and 14.4 keV spectra yields depth selective information about a sample and allows for the detection and characterization of thin coatings or weathering rinds. Laboratory measurements and a Monte Carlo simulation were used to study the influence of coatings of varying thickness and composition on backscattering Mössbauer spectra. The thickness of thin surface layers on natural samples can be estimated by comparing measured and the corresponding simulated spectra.

Keywords
Depth selective Mossbauer spectroscopy; Mars Exploration Rover mission; Iron mineralogy; Geochemistry

Journal
Hyperfine Interactions: Volume 186, Issue 1-3