0.25 Ga Salt Deposits Preserve Signatures of Habitable Conditions and Ancient Lipids

• DOI: 10.1089/ast.2019.2053
• Publication Date: 2020-04-14T18:50:57Z
• Authors: Charles S. Cockell; Mary Beth Wilhelm; Scott Perl; Jennifer Wadsworth; Sam Payler; Sean McMahon; Sean Paling; Thomas Edwards
• Keywords: Geologic Sediments; Minerals; Extraterrestrial Environment; Silicates; Mars; Quartz; Lipids; 01 natural sciences; United Kingdom; Chlorides; 13. Climate action; Exobiology; Aluminum Compounds; Weather; Biomarkers; 0105 earth and related environmental sciences

Polygonal features in a ∼250 million-year-old Permian evaporitic deposit were investigated for their geological and organic content to test the hypothesis that they could preserve signature of ancient habitable conditions biological activity. Investigations on rock carried out as part MIne Analog Research (MINAR) project at Boulby Mine, United Kingdom. The edges polygons have higher clay contain abundances minerals such quartz microcline, clays illite chlorite, compared with interior polygons, suggesting preferred locations accumulation weathering products during formation. mineral its strontium isotope ratio suggest material is from continental borders Zechstein Sea. mean δ13C δ15N values -20.8 5.3, respectively. Lipids, including alkanes hopanes, extracted which are inferred represent entrained evaporites when formed. presence long-chain (C20-C35) lack carbon preference, low C23-C29 marine, evaporitic, or thermal maturity indicators show lipid biomarkers were, least part, potentially derived source not undergone significant maturation since deposition. Lipid extractions using weak acids revealed significantly more lipids than those without acid, indicating encapsulation was only type preservation mechanism occurring salts. These data demonstrate potential information local conditions, habitability, evidence life. analogous martian deposits good targets future life detection missions investigation habitability.