Potential Antifreeze Compounds in Present-Day Martian Seepage Groundwater

Abstract

Is the recently found seepage groundwater on Mars pure H 2 O, or mixed with salts and other antifreeze compounds? Given the surface conditions of Mars, it is unlikely that pure water could either exist in its liquid state or have shaped Mars' fluid erosional landforms (gullies, channels, and valley networks). More likely is that Mars' seepage groundwater contains antifreeze and salt compounds that resist freezing and suppress evaporation. This model better accounts for Mars' enigmatic surface erosion. This paper suggests 17 antifreeze compounds potentially present in Martian seepage groundwater. Given their liquid state and physical properties, triethylene glycol, diethylene glycol, ethylene glycol, and 1,3-propylene glycol are advanced as the most likely candidate compounds. This paper also explores how a mixing of glycol or glycerol with salts in the Martian seepage groundwater may have lowered water's freezing point and raised its boiling point, with consequences that created fluid gully and channel erosion. Ethylene glycol and related hydrocarbon compounds have been identified in Martian and other interstellar meteorites. We suggest that these compounds and their proportions to water be included for detection in future explorations.

Enhanced runout and erosion by overland flow at low pressure and sub-freezing conditions: Experiments and application to Mars

“…Various compounds have been proposed to form solutions on Mars, which could facilitate the stability of water at low temperatures. Suggested compounds include: perchlorates (Catling et al, 2009;Hecht et al, 2009), Calcium Chloride (Knauth and Burt, 2002), Sodium Chloride (Sears et al, 2002), and Ferric Sulphate (Chevrier and Altheide, 2008) brines; organics (Jean et al, 2008) and acids (Benison et al, 2008). These all have a higher viscosity than pure water.…”