Assessment of Mars Analogue Instruments and Biosignatures in Icelandic Mars Analogue Environments: Implications for Astrobiology

To search more efficiently for a record of past life on Mars, it is critical to know where to look and thus maximize the likelihood of success. Large-scale site selection for the Mars 2020 mission has been completed, but small (meter to 10 cm)-scale relationships of microenvironments will not be known until the rover reaches the surface. This thesis aims to study different Icelandic Mars analog environments to simultaneously look at all domains of life interpreted in the context of the underlying mineralogical and geochemical environment. The overarching premise for this work is a comprehensive understanding of the geological and biological characteristics of terrestrial basaltic systems to better develop strategies to help guide the life-detection mission and sampling location selection to ensure best scientific return. This dissertation include 1) a study to describe an analogue mission in low biomass Mars analogue environments comparing the effectiveness, spatial variation, and inter-correlations of life-detection techniques and implications for Mars sampling selection 2) an examination of spatial distributions and levels of biosignatures in Icelandic Mars analogue environments 3) a study exploring the composition of microbial communities at different spatial scales in apparently homogenous environments, 4) final study linking biological indicators to physical characteristics including bulk chemical composition, spectral signatures of mineralogy, and grain size. The last chapter of the thesis will summarize major findings and present several recommendations for continued research.Ph.D