Thermal and Fluid Evolution of the Clearwater West Impact-Generated Hydrothermal System, Quebec, and Associated Astrobiological Implications
Abstract
Impact-generated hydrothermal systems result from interactions between a permeable substrate, an impact-generated heat source, and fluids (e.g., H2O). A comprehensive understanding of the evolution of these terrestrial features has significant implications in the search for habitable environments on Mars, a focus in the emerging field of astrobiology. This thesis presents a detailed case study of the impact-generated hydrothermal alteration of impactites at the Clearwater West impact structure, Quebec, focusing on hydrothermally precipitated quartz vugs in crater-fill impact melt rocks. Sample analysis included optical microscopy, electron microprobe analysis, mass spectrometry, and fluid inclusion microthermometry. Results show 3 main quartz mineralization stages: 1) > 384°C, 2) 382 to 246°C, and 3) 243 to 120°C. Gas analysis indicated volatile sources were primarily atmospheric, with some mixing of local magmatic and crustal sources. This research provides insight into water preservation on Mars and the significance of impact-generated hydrothermal systems for extraterrestrial microbial life.