Hydrothermal spring deposits host unique microbial ecosystems and have the capacity to preserve biosignatures within siliceous sinter layers. The discovery of hydrothermal deposits on Mars has recategorized hot springs as Mars-analog environments, driving forward the study of biosignature preservation in these settings to help prepare future missions. This study quantifies the hydrocarbon load in three Icelandic hot-spring deposits ranging from modern and inactive to relict.
Organics analyses were be performed with pyrolysis–gas chromatography–mass spectrometry (py-GC-MS). By exploring the preservation of organic matter from microbial extremophiles in terrestrial siliceous sinter, it is possible to extrapolate the degree of organic preservation possible for select hydrothermal sinter samples on Mars. The sinter samples for this project were collected at the surface and subsurface from 2 cm to 18 cm in depth from spring vent to distal apron to explore the coupling of system activity with preservation of biosignatures.
Preliminary results indicate a complex mixture of alkenes (C9 to C15), monounsaturated fatty acids (C6 & C9), and several aromatic molecules with variable methyl functional groups.
This study builds on Williams et al. (2020) by exploring the organics yield from samples treated with space flight-like pyrolysis GC-MS. Samples will be tested with both flash pyrolysis (at 600°C) and ramped pyrolysis (at 35°C/min and 200°C/min). As the Curiosity rover has encountered similar sinter on its traverse through Gale crater, it is crucial to understand how organics may be liberated from these rock types with space flight-like techniques.