Extraterrestrial hydrogeology

Abstract

Subsurface water processes are common for planetary bodies in the solar system and are highly probable for exoplanets (planets outside the solar system). For many solar system objects, the subsurface water exists as ice. For Earth and Mars, subsurface saturated zones have occurred throughout their planetary histories. Earth is mostly clement with the recharge of most groundwater reservoirs from ample precipitation during transient iceand hot-house conditions, as recorded through the geologic and fossilized records. On the other hand, Mars is mostly in an ice-house stage, which is interrupted by endogenic-driven activity. This activity catastrophically drives short-lived hydrological cycling and associated climatic perturbations. Regional aquifers in the Martian highlands that developed during past, more Earth-like conditions delivered water to the northern plains. Water was also cycled to the South Polar Region during changes in climate induced by endogenic activity and/or by changes in Mars' orbital parameters. Venus very likely had a warm hydrosphere for hundreds of millions of years, before the development of its current extremely hot atmosphere and surface. Subsequently, Venus lost its hydrosphere as solar luminosity increased and a run-away moist greenhouse took effect. Subsurface oceans of water or ammonia-water composition, induced by tidal forces and radiogenic heating, probably occur on the larger satellites Europa, Ganymede, Callisto, Titan, and Triton. Tidal forces operating between some of the small bodies of the outer solar system could also promote the fusion of ice and the stability of inner liquid-water oceans.RØsumØ Les processus de subsurface impliquant l'eau sont communs pour les corps planØtaires du syst me solaire et sont tr s probables sur les exoplan tes (plan tes en dehors du syst me solaire). Pour plusieurs objets du syst mes solaire, l'eau de subsurface est prØsente sous forme de glace. Pour la Terre et Mars, les zones saturØes de subsurface apparaissent à travers toute leur histoire planØtaire. La Terre est particuli rement clØmente avec la recharge des rØservoirs, avec de amples prØcipitations, des conditions glaciaires et de fortes chaleurs, comme l'atteste les enregistrements gØologiques et palØontologiques. D'un autre côtØ, Mars se trouve dans une phase essentiellement glaciaire, qui est interrompue par des activitØs contraintes par les phØnom nes endogØniques. Cette activitØ conduit de mani re catastrophique à des cycles hydrologiques et à des perturbations climatiques brutaux. Les aquif res rØgionaux dans les haute terres martiennes qui se sont formØs dans des conditions similaires aux conditions terrestres, alimentent les plaines du Nord. Resumen Los procesos hídricos subsuperficiales son comunes en cuerpos planetarios del sistema solar y son altamente probables para exoplanetas (planetas fuera del sistema solar). Para muchos cuerpos del sistema solar, el agua subsuperficial existe como hielo. Para la Tierra y Marte han ocurrido zonas saturadas subsuperficiales a travØ...

Modeling ammonia–ammonium aqueous chemistries in the Solar System’s icy bodies

“…Theory suggests that there may be subsurface water oceans on Titan (Fortes, 2000;Baker et al, 2005;Tobie et al, 2005;Fortes et al, 2007;Sotin and Tobie, 2008;Sohl et al, 2010) that are today as close to 50 km of the surface and for much of the past may have been within 10-20 km (Tobie et al, 2005).…”

“…Interest in possible sequestration of ammonia in ammonium solids and reactive destruction of ammonia (Kargel, 1992) has renewed timeliness to help explain why ammonia is rarely observed despite decades of searching for it. Recent investigations on the nature of internal fluids on icy moons has been stimulated by the Cassini-Huygens Mission (Baker et al, 2005;Tobie et al, 2005;Hussmann et al, 2006;Waite et al, 2006;Fortes et al, 2007;Spencer and Grinspoon, 2007;Smythe et al, 2009;Waite et al, 2009Waite et al, , 2011Zolotov et al, 2011) and is pertinent to the upcoming Pluto/Charon/Kuiper Belt mission of New Horizons. On Earth, aqueous ammonia and ammonium salts are important in biology; the chemistries dealt with in this work may also have astrobiological consequences, which we briefly explore.…”

“…The completed Galileo mission to the Jupiter system and the continuing Cassini-Huygens mission to Saturn and its satellites, and the anticipation of the New Horizons flyby of the Pluto system and the Dawn mission that will orbit Ceres have stimulated considerable new thinking about the geochemical evolution of Europa, Enceladus, Titan, Pluto, outer main belt asteroids, and other icy bodies (Kargel et al, 2000;Baker et al, 2005;Cruikshank et al, 2005;Brown et al, 2006;Hussmann et al, 2006;Kieffer et al, 2006;Spencer et al, 2006;Waite et al, 2006Waite et al, , 2009Waite et al, , 2011Yokano et al, 2006;Fortes, 2007Fortes, , 2012Fortes et al, 2007;Manga and Wang, 2007;Matson et al, 2007;Nimmo et al, 2007;Parkinson et al, 2007;Spencer and Grinspoon, 2007;Zolotov, 2007;Grindrod et al, 2008;Kieffer and Jakosky, 2008;McKinnon et al, 2008;Sotin and Tobie, 2008;Cooper et al, 2009;Postberg et al, 2009Postberg et al, , 2011Zolotov and Kargel, 2009;Sohl et al, 2010;Zolotov et al, 2011). Among the questions concerning the icy moons of the outer planets is the relevance of ammonia and ammonium compounds.…”

Evidences for a Noachian–Hesperian orogeny in Mars

“…In this paper we present the results of a critical revision of images which show that in Noachian times Mars experienced tectonic processes amounting, in range and intensity, to what in Earth geology we would term an orogeny. Spagnuolo and Dohm (2004) have been the first authors to use the word orogeny for Mars, though the associated expressions "mountain ranges" and "mountain building" have been introduced in descriptions ( Scott and Tanaka, 1981;Dohm et al, 2002;Baker et al, 2005) of the reliefs of at least an area peripheral to Tharsis province: the Thaumasia Highlands. It is also true that the authors (Connerney et al, 1999;Nimmo and Stevenson, 2000;Zhong and Zuber, 2001;Hauberg and Kronberg, 2001;Fairén et al, 2002;Baker et al, 2002;Dohm et al, 2002;Fairén and Dohm, 2004) that have defended some form of martian plate tectonics theory are implicitly sustaining the existence of structural belts similar (?)…”

WatSen: searching for clues for water (and life) on Mars

“…Under a 'warmer and wetter ' regime, with pervasive and persistent bodies of standing water, there would be an extended hydrological cycle in operation. In contrast, a ' cold and dry' climate for most of Mars' history would curtail any hydrological cycle (Baker et al 2005). The difference between the two climate models is of great significance for the potential evolution of life on Mars.…”