Serpentinization is a common water-rock reaction in our solar system, and is likely responsible for producing reducing conditions capable of driving abiotic organic synthesis on the early Earth, and potentially on icy worlds such as Enceladus and Europa. Accordingly, knowledge of this process is fundamental to directing and understanding our observations of extraterrestrial bodies, which may possess surface signatures as a result. This potential for abiotic organic synthesis makes modern low temperature serpentinizing systems attractive sites to investigate for understanding volatile production, prebiotic chemistry, and for characterizing the propensity of serpentinization to generate habitable conditions. Because low temperature terrestrial systems can support life, however, it is very difficult to disentangle which organic compounds measured in natural systems are produced biologically, thermogenically (breakdown of biomass), or abiotically. Experiments are a very useful tool, especially for getting after reaction rates, but at low temperatures certain abiotic reactions which may occur over geologic time scales cannot be observed. Nevertheless, headway in the field is being made via a multi-pronged approach whereby thermodynamic analyses, stable isotope tracer/tracking methods, and chemical mechanism probing techniques are applied to field measurements, abiotic experiments, and biological cultures. I will discuss the progress and caveats of these techniques in the context of natural systems.
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