THE INFLUENCE OF TEMPERATURE ON MICROBIAL COLONIZATION, CRATERS OF THE MOON NATIONAL MONUMENT, IDAHO: IMPLICATIONS FOR BIOSIGNATURE FORMATION WITHIN “SPECIAL REGIONS” ON MARS
Our pilot study will systematically link microtextures and mineralogy with microbial processes under three cave climate regimes (1) water:rock, (2) water/ice:rock, and (3) ice:rock systems all within a 1.6 km area at Craters of the Moon National Monument (CROM). Aqueous samples collected from the caves indicate cave waters may derive from a similar source, based on similarities in Cl- (1.6-1.8 mg L-1) and SO42-(2.1-3.8 mg L-1), however, temperatures vary from 10oC (water:rock) to 0oC (ice:rock) conditions. Using a combination of scanning electron microscopy, X-ray diffraction, ICP-OES, and ion chromatography we will (1) quantify microbial colonization and (2) determine textures, and products of chemical and microbial weathering in lava caves experiencing differing water/ice:rock interactions.
CROM is an excellent analog for Mars because (1) the basalts are geochemically similar in major and trace elements and (2) the field site is classified as a cold, semi-arid region, similar to conditions that may have existed on Mars in the late-Noachian to present. Results from this study will aid in the definition of chemical and microbial biosignatures formed under different lava cave climate conditions and in turn aid in our assessment of Mars’s habitability.