Impact‐induced hydrothermal activity on early Mars

[1] We report on numerical modeling results of postimpact cooling of craters with diameters of 30, 100, and 180 km in an early Martian environment, with and without the presence of water. The effects of several variables, such as ground permeability and the presence of a crater lake, were tested. Host rock permeability is the main factor affecting fluid circulation and lifetimes of hydrothermal systems, and several permeability cases were examined for each crater. The absence of a crater lake decreases the amount of circulating water and increases the system lifetime; however, it does not dramatically change the character of the system as long as the ground remains saturated. It was noted that vertical heat transport by water increases the temperature of localized near-surface regions and can prolong system lifetime, which is defined by maximum near-surface temperature. However, for very high permeabilities this effect is negated by the overall rapid cooling of the system. System lifetimes, which are defined by near-surface temperatures and averaged for all permeability cases examined, were 67,000 years for the 30-km crater, 290,000 years for the 100-km crater, and 380,000 for the 180-km crater. Also, an approximation of the thermal evolution of a Hellas-sized basin suggests potential for hydrothermal activity for ∼10 Myr after the impact. These lifetimes provide ample time for colonization of impact-induced hydrothermal systems by thermophilic organisms, provided they existed on early Mars. The habitable volume reaches a maximum of 6,000 km 3 8,500 years after the impact in the 180-km crater model.

[1]  D. Kring,et al.  Hydrothermal alteration in the core of the Yaxcopoil‐1 borehole, Chicxulub impact structure, Mexico , 2004 .

[2]  D. Ames,et al.  Dating of a regional hydrothermal system induced by the 1850 Ma Sudbury impact event , 1998 .

[3]  Jeffrey R. Johnson,et al.  In Situ Evidence for an Ancient Aqueous Environment at Meridiani Planum, Mars , 2004, Science.

[4]  H. Melosh,et al.  Melt Production in Oblique Impacts , 1999 .

[5]  G. B. Dalrymple,et al.  Argon-40/Argon-39 Age Spectra of Apollo 17 Highlands Breccia Samples by Laser Step Heating and the Age of the Serenitatis Basin , 1996 .

[6]  Richard J. Pike,et al.  Size-dependence in the shape of fresh impact craters on the moon , 1977 .

[7]  Nathalie A. Cabrol,et al.  Limnologic Analysis of Gusev Crater Paleolake, Mars , 1997 .

[8]  M. Naumov Impact-Generated Hydrothermal Systems: Data from Popigai, Kara, and Puchezh-Katunki Impact Structures , 2002 .

[9]  David A. Kring,et al.  Cataclysmic bombardment throughout the inner solar system 3.9–4.0 Ga , 2002 .

[10]  Steven W. Squyres,et al.  Ice in the Martian regolith , 1992 .

[11]  V. Gulick Some Ground Water Considerations Regarding the Formation of Small Martian Gullies , 2001 .

[12]  Stephen M. Clifford,et al.  A model for the hydrologic and climatic behavior of water on Mars , 1993 .

[13]  V. Shuvalov,et al.  Numerical simulations of the Mjlnir marine impact crater , 2002 .

[14]  M. Nordyke CRATERING EXPERIENCE WITH CHEMICAL AND NUCLEAR EXPLOSIVES , 1964 .

[15]  Michael H. Carr,et al.  Water on Mars , 1987, Nature.

[16]  G. Brass,et al.  Stability of brines on Mars , 1980 .

[17]  D. Uhlmann,et al.  The thermal history of the Manicouagan Impact Melt Sheet, Quebec , 1978 .

[18]  B. Cohen,et al.  Support for the lunar cataclysm hypothesis from lunar meteorite impact melt ages. , 2000, Science.

[19]  Donald L. Turcotte,et al.  Mantle Convection in the Earth and Planets , 2001 .

[20]  D. A. Papanastassiou,et al.  Isotopic evidence for a terminal lunar cataclysm , 1974 .

[21]  J. Garvin,et al.  A geometric model for excavation and modification at terrestrial simple impact craters , 1984 .

[22]  N. Pace A molecular view of microbial diversity and the biosphere. , 1997, Science.

[23]  Alfred S. McEwen,et al.  Rootless cones on Mars indicating the presence of shallow equatorial ground ice in recent times , 2001 .

[24]  M. Mellon,et al.  Laboratory simulations of Mars aqueous geochemistry , 2004 .

[25]  B. Ivanov,et al.  Sudbury impact event: Cratering mechanics and thermal history , 1999 .

[26]  L. Crossey,et al.  Post-impact hydrothermal alteration of the Manson impact structure , 1996 .

[27]  P. A. J. Englert,et al.  Distribution of Hydrogen in the Near Surface of Mars: Evidence for Subsurface Ice Deposits , 2002, Science.

[28]  S. Kieffer,et al.  The role of volatiles and lithology in the impact cratering process. , 1980 .

[29]  H. Newsom Hydrothermal alteration of impact melt sheets with implications for Mars , 1980 .

[30]  H. Melosh Impact Cratering: A Geologic Process , 1986 .

[31]  R. J. Pike SOME MORPHOLOGIC SYSTEMATICS OF COMPLEX IMPACT STRUCTURES , 1985 .

[32]  D. H. Watkinson,et al.  Alteration and the role of fluids in Ni, Cu and platinum-group element deposition, Sudbury Igneous Complex contact, Onaping-Levack area, Ontario , 1992 .

[33]  B. Ivanov,et al.  Starting Conditions for Hydrothermal Systems Underneath Martian Craters: Hydrocode Modeling , 2003 .

[34]  James W. Head,et al.  Comparison of impact basins on Mercury, Mars and the moon , 1976 .

[35]  Robert O. Foumier The transition from hydrostatic to greater than hydrostatic fluid pressure in presently active continental hydrothermal systems in crystalline rock , 1991 .

[36]  Roger J. Phillips,et al.  Morphometric measurements of martian valley networks from Mars Orbiter Laser Altimeter (MOLA) data , 2001 .

[37]  W. Ernst Petrologic Phase Equilibria , 1976 .

[38]  N. Cabrol,et al.  Recent aqueous environments in Martian impact craters: an astrobiological perspective , 2001 .

[39]  A. Davaille,et al.  Thermal convection in lava lakes , 1993 .

[40]  Alan B. Binder,et al.  On the thermal history, thermal state, and related tectonism of a moon of fission origin , 1980 .

[41]  P. Mouginis-Mark,et al.  A Very Young, Large, Impact Crater on Mars , 2003 .

[42]  M. Pilkington,et al.  Secondary alteration of the impactite and mineralization in the basal Tertiary sequence, Yaxcopoil‐1, Chicxulub impact crater, Mexico , 2004 .

[43]  A. Babeyko,et al.  Martian crust: a modeling approach , 2000 .

[44]  A. Colaprete,et al.  Environmental Effects of Large Impacts on Mars , 2002, Science.

[45]  D. Kring,et al.  Numerical modeling of an impact‐induced hydrothermal system at the Sudbury crater , 2003 .

[46]  P. Mouginis-Mark Water or ice in the Martian regolith?: Clues from rampart craters seen at very high resolution , 1987 .

[47]  Pascal Lee,et al.  Impact‐induced hydrothermal activity within the Haughton impact structure, arctic Canada: Generation of a transient, warm, wet oasis , 2001 .

[48]  N. Sleep Hydrothermal circulation, anhydrite precipitation, and thermal structure at ridge axes , 1991 .

[49]  W. Boynton,et al.  Petrogenesis of an augite-bearing melt rock in the Chicxulub structure and its relationship to K/T impact spherules in Haiti , 1992, Nature.

[50]  Alan D. Howard,et al.  The case for rainfall on a warm, wet early Mars , 2002 .

[51]  Thomas J. Ahrens,et al.  Shock melting and vaporization of lunar rocks and minerals , 1972 .

[52]  S. Ingebritsen,et al.  Multiphase groundwater flow near cooling plutons , 1997 .

[53]  E. Pierazzo,et al.  Numerical modeling of impact heating and cooling of the Vredefort impact structure , 2003 .

[54]  Mark J. Cintala,et al.  Scaling impact melting and crater dimensions: Implications for the lunar cratering record , 1998 .

[55]  Water soluble ions in the Nakhla martian meteorite , 2000 .

[56]  A. Wittmann,et al.  Composition of impact melt particles and the effects of post‐impact alteration in suevitic rocks at the Yaxcopoil‐1 drill core, Chicxulub crater, Mexico , 2004 .

[57]  H. Newsom,et al.  Availability of Heat to Drive Hydrothermal Systems in Large Martian Impact Craters , 2001 .

[58]  N. Sleep,et al.  Impacts and the Early Evolution of Life , 2006 .

[59]  N. Barlow,et al.  Martian impact crater ejecta morphologies as indicators of the distribution of subsurface volatiles , 2003 .

[60]  C. Allen,et al.  Hydrothermally altered impact melt rock and breccia: Contributions to the soil of Mars , 1982 .

[61]  K. Holsapple THE SCALING OF IMPACT PROCESSES IN PLANETARY SCIENCES , 1993 .

[62]  S. Squyres,et al.  Hydrothermal systems associated with martian impact craters , 2002 .

[63]  B. Ivanov Heating of the Lithosphere during Meteorite Cratering , 2004 .

[64]  N. Cabrol,et al.  Distribution, Classification, and Ages of Martian Impact Crater Lakes , 1999 .

[65]  C. Hibbitts,et al.  Impact crater lakes on Mars , 1996 .

[66]  U. Schärer,et al.  Impact melt dikes in the Sudbury multi-ring basin (Canada): Implications from uranium-lead geochronology on the Foy Offset Dike , 1996 .

[67]  S. Wood,et al.  Experimental hydrothermal alteration of a martian analog basalt: Implications for martian meteorites , 2000 .

[68]  Bruce D. Marsh,et al.  The convective liquidus in a solidifying magma chamber: a fluid dynamic investigation , 1989, Nature.

[69]  G. B. Dalrymple,et al.  40Ar/39Ar age spectra of Apollo 15 impact melt rocks by laser step‐heating and their bearing on the history of lunar basin formation , 1993 .

[70]  Joshua L. Bandfield,et al.  A Global View of Martian Surface Compositions from MGS-TES , 2000 .

[71]  S. Ingebritsen,et al.  The computer model Hydrotherm, a three-dimensional finite-difference model to simulate ground-water flow and heat transport in the temperature range of 0 to 1,200 degrees C , 1994 .

[72]  D. Bogard Impact ages of meteorites: A synthesis , 1995 .

[73]  D. Kring The dimensions of the Chicxulub impact crater and impact melt sheet , 1995 .

[74]  R. Grieve,et al.  Volumetric analysis of complex lunar craters: Implications for basin ring formation , 1982 .

[75]  S. Mojzsis,et al.  Vestiges of a beginning: Clues to the emergent biosphere recorded in the oldest known sedimentary rocks , 2000 .

[76]  E. Shock,et al.  Hydrothermal hydration of Martian crust: illustration via geochemical model calculations. , 1997, Journal of geophysical research.

[77]  R. Grieve,et al.  Cratering processes: as interpreted from the occurrence of impact melts. , 1977 .

[78]  H. Newsom,et al.  Location and sampling of aqueous and hydrothermal deposits in martian impact craters. , 2001, Astrobiology.