Seminar

Life emerged in what is by definition a “habitable” environment on the early Earth. While 99.9% of the early crust on Earth has been destroyed due to plate tectonics and erosion, Mars retains a large portion of its ancient crust, with minimal metamorphism (80 % surface >3.8 Ga). Unlike the cold, dry and oxidized surface environment of Mars today, ancient Mars shows evidence of extensive lakes, channels, and even oceans or seas represented by aqueous minerals tracing sedimentary and hydrothermal environments. In this talk, I will explore different habitable environments on Mars, including weathering profiles, lakes, possible mud volcanoes and serpentinite-hosted hydrothermal systems of early Mars. I argue that the duration of these aqueous activities may have been geologically short, accounting for only a small fraction of the prolonged martian history. The early Martian subsurface was perhaps more stable over long periods of harsh surface conditions, providing a continuously habitable environment. In summary, this talk describes the dynamic habitability of Mars over time, from climate-surface interactions to the deep subsurface hydrothermal system, from orbital kilometer scales down to microscopic scales of analog rocks studied in the laboratory.

Additional information: Mr. YE Binlong, binlongy@hku.hk