Natural fumarolic alteration of fluorapatite, olivine, and basaltic glass, and implications for habitable environments on Mars

Astrobiology

Volumn 13, Issue 11, 2013, Pages 1049-1064

  Hausrath, Elisabeth M ^a   Tschauner, Oliver ^a  

^a UNIVERSITY OF NEVADA   (United States)

Author keywords

Acidophile; Fumaroles; Geothermal; Mars; Olivine; Search for life (biosignatures); Synchrotron X ray diffraction

Indexed keywords

APATITE; FLUORAPATITE; GLASS; IRON DERIVATIVE; MAGNESIUM DERIVATIVE; OLIVINE; SILICATE;

ARTICLE; ASTRONOMY; BASALT; CHEMISTRY; GEOGRAPHIC AND GEOLOGICAL PHENOMENA; LIFE; MICROCLIMATE;

APATITES; EXTRATERRESTRIAL ENVIRONMENT; GEOLOGICAL PHENOMENA; GLASS; IRON COMPOUNDS; LIFE; MAGNESIUM COMPOUNDS; MARS; SILICATES;

EID: 84890239398     PISSN: 15311074     EISSN: None     Source Type: Journal    
DOI: 10.1089/ast.2013.0985     Document Type: Article

References (117)

1. Adcock, C.T., Hausrath, E.M., and Forster, P. (2013) Readily available phosphate from minerals in early aqueous environments on Mars. Nat Geosci 6:824-827.
2. Albertano, P., Ciniglia, C., Pinto, G., and Pollio, A. (2000) The taxonomic position of Cyanidium, Cyanidioschyzon and Galdieria: an update. Hydrobiologia 433:137-143.
3. Allen, C.C. and Oehler, D.Z. (2008) A case for ancient springs in Arabia Terra, Mars. Astrobiology 8:1093-1112.
4. Augusto, L., Turpault, M.-P., and Ranger, J. (2000) Impact of forest tree species on feldspar weathering rates. Geoderma 96:215-237.
5. Awad, A., van Groos, A.F.K., and Guggenheim, S. (2000) Forsteritic olivine: effect of crystallographic direction on dissolution kinetics. Geochim Cosmochim Acta 64:1765-1772.
6. Banin, A., Han, F.X., Kan, I., and Cicelsky, A., (1997) Acidic volatiles and the Mars soil. J Geophys Res 102:13341-13356.
7. Bennett, P.C., Hiebert, F.K., and Choi, W.J. (1996) Microbial colonization and weathering of silicates in a petroleum-contaminated groundwater. Chem Geol 132:45-53.
8. Bergfeld, D., Goff, F., and Janik, C.J. (2001) Elevated carbon dioxide flux at the Dixie Valley geothermal field, Nevada; relations between surface phenomena and the geothermal reservoir. Chem Geol 177:43-66.
9. Blum, A.E. and Lasaga, A.C. (1988) Role of surface speciation in the low-temperature dissolution of minerals. Nature 331: 431-433.
10. Brady, P.V. and Walther, J.V. (1989) Controls on silicate dissolution rates in neutral and basic pH solutions at 25-C. Geochim Cosmochim Acta 53:2823-2830.
11. Casciani, F. and Condrate, R.A. (1980) The Raman spectrum of monetite. J Solid State Chem 34:385-388.
12. Cha?̈rat, C., Schott, J., Oelkers, E.H., Lartigue, J.-E., and Harouiya, N. (2007) Kinetics and mechanism of natural fluorapatite dissolution at 25-C and pH from 3 to 12. Geochim Cosmochim Acta 71:5901-5912.
13. Chaudhry, A.A., Knowles, J.C., Rehman, I., and Darr, J.A. (2012) Rapid hydrothermal flow synthesis and characterisation of carbonate-and silicate-substituted calcium phosphates. J Biomater Appl 28:448-461.
14. Chopelas, A. (1991) Single crystal Raman spectra of forsterite, fayalite and monticellite. Am Mineral 76:1101-1109.
15. Costello, E.K., Halloy, S.R.P., Reed, S.C., Sowell, P., and Schmidt, S.K. (2009) Fumarole-supported islands of biodiversity within a hyperarid, high-elevation landscape on Socompa Volcano, Puna de Atacama, Andes. Appl Environ Microbiol 75:735-747.
16. David, W.I.F., Shankland, K., McCusker, L.B., and Baerlocher, C. (2006) Structure Determination from Powder Diffraction Data, International Union of Crystallography Monographs on Crystallography 13, Oxford University Press, Oxford.
17. Demartin, F., Campostrini, I., and Gramaccioli, C.M. (2009a) Panichiite, natural ammonium hexachlorostannate(iv), (NH4)2SnCl6, from La Fossa Crater, Vulcano, Aeolian Islands, Italy. Can Mineral 47:367-372.
18. Demartin, F., Gramaccioli, C.M., and Campostrini, I. (2009b) Brontesite, (NH4)3PbCl5, a new product of fumarolic activity from La Fossa Crater, Vulcano, Aeolian Islands, Italy. Can Mineral 47:1237-1243.
19. Demartin, F., Gramaccioli, C.M., and Campostrini, I. (2010a) Adranosite, (NH4)4NaAI2(SO4)4CI(OH)2, a new ammonium sulfate chloride from La Fossa Crater, Vulcano, Aeolian Islands, Italy. Can Mineral 48:315-321.
20. Demartin, F., Gramaccioli, C.M., and Campostrini, I. (2010b) Pyracmonite, (NH4)3Fe(SO4)3, a new ammonium iron sulfate from La Fossa Crater, Vulcano, Aeolian Islands, Italy. Can Mineral 48:307-313.
21. D?́az, F.J., O'Geen, A.T., Rasmussen, C., and Dahlgren, R.A. (2010) Pedogenesis along a thermal gradient in a geothermal region of the southern Cascades, California. Geoderma 154: 495-507.
22. Dill, H.G., Melcher, F., Gerdes, A., and Weber, B. (2008) The origin and zoning of hypogene and supergene Fe-Mn-Mg-Sc-U-REE phosphate mineralization from the newly discovered trutzhofmuhle aplite, Hagendorf pegmatite province, Germany. Can Mineral 46:1131-1157.
23. Dixon, J.C., Thorn, C.E., Darmody, R.G., and Schlyter, P. (2001) Weathering rates of fine pebbles at the soil surface in Karkevagge, Swedish Lapland. Catena 45:273-286.
24. Dixon, J.C., Campbell, S.W., Thorn, C.E., and Darmody, R.G. (2006) Incipient weathering rind development on introduced machine-polished granite discs in an Arctic alpine environment, northern Scandinavia. Earth Surface Processes and Landforms 31:111-121.
25. Downs, R.T. (2006) The RRUFF project: an integrated study of the chemistry, crystallography, Raman and infrared spectroscopy of minerals [abstract 003-13]. In 19th General Meeting of the International Mineralogical Association, International Mineralogical Association, Kobe, Japan.
26. Edwards, H.G.M. (2004) Raman spectroscopic protocol for the molecular recognition of key biomarkers in astrobiological exploration. Orig Life Evol Biosph 34:3-11.
27. Edwards, H.G.M. (2007) Question 2: Raman spectroscopic approach to analytical astrobiology: the detection of key biomolecular markers in the search for life. Orig Life Evol Biosph 37:335-339.
28. Edwards, H.G.M., Newton, E.M., Dickensheets, D.L., and Wynn-Williams, D.D. (2003) Raman spectroscopic detection of biomolecular markers from Antarctic materials: evaluation for putative martian habitats. Spectrochim Acta A Mol Biomol Spectrosc 59:2277-2290.
29. Edwards, H.G.M., Jorge Villar, S.E., Bishop, J.L., and Bloomfield, M. (2004a) Raman spectroscopy of sediments from the Antarctic Dry Valleys; an analogue study for exploration of potential paleolakes on Mars. J Raman Spectrosc 35:458-462.
30. Edwards, H.G.M., Moody, C.A., Jorge Villar, S.E., and Mancinelli, R. (2004b) Raman spectroscopy of desert varnishes and their rock substrata. J Raman Spectrosc 35:475-479.
31. Edwards, H.G.M., Moody, C.D., Jorge Villar, S.E., and Wynn-Williams, D.D. (2005) Raman spectroscopic detection of key biomarkers of cyanobacteria and lichen symbiosis in extreme Antarctic habitats: evaluation for Mars lander missions. Icarus 174:560-571.
32. Edwards, H.G.M., Mohsin, M., Sadooni, F., Nik Hassan, N., and Munshi, T. (2006) Life in the sabkha: Raman spectroscopy of halotrophic extremophiles of relevance to planetary exploration. Anal Bioanal Chem 385:46-56.
33. Edwards, H.G.M., Vandenabeele, P., Jorge-Villar, S.E., Carter, E.A., Perez, F.R., and Hargreaves, M.D. (2007a) The R?́o Tinto Mars analogue site: an extremophilic Raman spectroscopic study. Spectrochim Acta A Mol Biomol Spectrosc 68:1133-1137.
34. Edwards, H.G.M., Jorge Villar, S.E., Pullan, D., Hargreaves, M.D., Hofmann, B.A., and Westall, F. (2007b) Morphological biosignatures from relict fossilised sedimentary geological specimens: a Raman spectroscopic study. J Raman Spectrosc 38:1352-1361.
35. Ehlmann, B.L.,Mustard, J.F., Swayze, G.A., Clark, R.N., Bishop, J.L., Poulet, F., Des Marais, D.J., Roach, L.H., Milliken, R.E., Wray, J.J., Barnouin-Jha, O., and Murchie, S.L. (2009). Identification of hydrated silicate minerals on Mars using MROCRISM: geologic context near Nili Fossae and implications for aqueous alteration. J Geophys Res 114, doi:10.1029/ 2009JE003339.
36. Ehlmann, B.L., Mustard, J.F., and Murchie, S.L. (2010) Geologic setting of serpentine deposits on Mars. Geophys Res Lett 37, doi:10.1029/2010GL042596.
37. Ehlmann, B.L., Mustard, J.F., Clark, R.N., Swayze, G.A., and Murchie, S.L. (2011) Evidence for low-grade metamorphism, hydrothermal alteration, and diagenesis on Mars from phyllosilicate mineral assemblages. Clays Clay Miner 59:359-377.
38. Eick, M.J., Grossl, P.R., Golden, D.C., Sparks, D.L., and Ming, D.W. (1996a) Dissolution kinetics of a lunar glass simulant at 25 degrees C: the effect of pH and organic acids. Geochim Cosmochim Acta 60:157-170.
39. Eick, M.J., Grossl, P.R., Golden, D.C., Sparks, D.L., and Ming, D.W. (1996b) Dissolution of a lunar basalt simulant as affected by pH and organic anions. Geoderma 74:139-160.
40. Ellis, D.G., Bizzoco, R.W., and Kelley, S.T. (2008) Halophilic Archaea determined from geothermal steam vent aerosols. Environ Microbiol 10:1582-1590.
41. Eriksson, E. (1982) On the rate of dissolution of olivine in aqueous solutions. Vatten 38:409-415.
42. Filiberto, J. and Treiman, A.H. (2009) Martian magmas contained abundant chlorine, but little water. Geology 37:1087-1090.
43. Fleet, M.E. and Xiaoyang, L. (2003) Carbonate apatite type A synthesized at high pressure: new space group (P3-) and orientation of channel carbonate ion. J Solid State Chem 174: 412-417.
44. Frausto da Silva, J.J.R. and Williams, R.J.P. (1991) The Biological Chemistry of the Elements, Clarendon Press, Oxford, UK.
45. Garavelli, A., Laviano, R., and Vurro, F. (1997) Sublimate deposition from hydrothermal fluids at the Fossa Crater-Vulcano, Italy. European Journal of Mineralogy 9:423-432.
46. Gislason, S.R. and Eugster, H.P. (1987) Meteoric water-basalt interactions. I: A laboratory study. Geochim Cosmochim Acta 51:2827-2840.
47. Gislason, S.R. and Oelkers, E.H. (2003) Mechanism, rates and consequences of basaltic glass dissolution: II An experimental study of the dissolution rates of basaltic glass as a function of pH and temperature. Geochim Cosmochim Acta 67:3817-3832.
48. Goff, F., Bergfeld, D., Janik, C.J., Counce, D., and Murrell, M. (2002) Geochemical Data on Waters, Gases, Scales, and Rocks from the Dixie Valley Region, Nevada (1996-1999), Los Alamos National Laboratory, Los Alamos, NM.
49. Golden, D.C., Ming, D.W., Morris, R.V., and Mertzman, S.A. (2005) Laboratory-simulated acid-sulfate weathering of basaltic materials: implications for formation of sulfates at Meridiani Planum and Gusev Crater, Mars. J Geophys Res 110, doi:10.1029/2005JE002451.
50. Grandstaff, D.E. (1980) The dissolution of forsteritic olivine from Hawaiian beach sand. In Third International Symposium onWater-Rock Interaction, WRI-3, International Association of Geochemistry and Cosmochemistry, Edmonton, Canada, pp 72-74.
51. Grandstaff, D.E. (1986) The dissolution rate of forsteritic olivine from Hawaiian beach sand. In Rates of Chemical Weathering of Rocks and Minerals, edited by S.M. Colman and D.P. Dethier, Academic Press, New York, pp 41-59.
52. Gudbrandsson, S., Wolff-Boenisch, D., Gislason, S.R., and Oelkers, E.H. (2008) Dissolution rates of crystalline basalt at pH 4 and 10 and 25-75-C. Mineral Mag 72:155-158.
53. Halloy, S. (1991) Islands of life at 6000maltitude-the environment of the highest autotrophic communities on Earth (Socompa Volcano, Andes). Arctic and Alpine Research 23:247-262.
54. Hammersley, A., Svensson, S., and Hanfland, M. (1996) Twodimensional detector software: from real detector to idealised image or two-theta scan. High Press Res 14:235-248.
55. Hausrath, E.M. and Brantley, S.L. (2010) Basalt and olivine dissolution under cold, salty, and acidic conditions: what can we learn about recent aqueous weathering on Mars? J Geophys Res 115, doi:10.1029/2010JE003610.
56. Hausrath, E.M. and Olsen, A.A. (2013) Using the chemical composition of carbonate rocks on Mars as a record of secondary interaction with liquid water. Am Mineral 98:897-906.
57. Hausrath, E.M., Liermann, L.J., House, C.H., Ferry, J.G., and Brantley, S.L. (2007) The effect of methanogen growth on mineral substrates: will Ni markers of methanogen-based communities be detectable in the rock record? Geobiology 5:49-61.
58. Hausrath, E.M., Navarre-Sitchler, A.K., Sak, P.B., Steefel., C.I., and Brantley, S.L. (2008a) Basalt weathering rates on Earth and the duration of liquid water on the plains of Gusev Crater, Mars. Geology 36:67-70.
59. Hausrath, E.M., Treiman, A.H., Vicenzi, E., Bish, D.L., Blake, D., Sarrazin, P., Hoehler, T., Midtkandal, I., Steele, A., and Brantley, S.L. (2008b) Short-and long-term olivine weathering in Svalbard: implications for Mars. Astrobiology 8:1079-1092.
60. Hausrath, E.M., Golden, D.C., Morris, R.V., Agresti, D.G., and Ming, D.W. (2013) Acid sulfate alteration of fluorapatite, basaltic glass and olivine by hydrothermal vapors and fluids: implications for fumarolic activity and secondary phosphate phases in sulfate-rich Paso Robles soil at Gusev Crater, Mars. J Geophys Res Planets 118:1-13.
61. Hawthorne, F.C. (1998) Structure and chemistry of phosphate minerals. Mineral Mag 62:141-164.
62. Hedenquist, J.W. (2000) Exploration for epithermal gold deposits. SEG Reviews 13:245-277.
63. Horgan, B. and Bell, J.F. (2012) Widespread weathered glass on the surface of Mars. Geology 40:391-394.
64. Hurowitz, J.A., McLennan, S.M., McSween, H.Y., DeSouza, P.A.J., and Klingelhofer, G. (2006) Mixing relationships and the effects of secondary alteration in the Wishstone and Watchtower Classes of Husband Hill, Gusev Crater, Mars. J Geophys Res 111, doi:10.1029/2006JE002795.
65. Hynek, B.M., McCollom, T.M., and Rogers, K.L. (2011) Cerro Negro volcano, Nicaragua: an assessment of geological and potential biological systems on early Mars. Geological Society of America Special Papers 483:279-285.
66. Jehli-cka, J. and Edwards, H.G.M. (2008) Raman spectroscopy as a tool for the non-destructive identification of organic minerals in the geological record. Org Geochem 39:371-386.
67. Jehli-cka, J., Edwards, H.G.M., and V?́tek, P. (2009) Assessment of Raman spectroscopy as a tool for the non-destructive identification of organic minerals and biomolecules for Mars studies. Planet Space Sci 57:606-613.
68. Jonckbloedt, R.C.L. (1998) Olivine dissolution in sulphuric acid at elevated temperatures: implications for the olivine process, an alternative waste acid neutralizing process. J Geochem Explor 62:337-346.
69. Jorge Villar, S.E., Edwards, H.G.M., and Cockell, C.S. (2005) Raman spectroscopy of endoliths from Antarctic cold desert environments. Analyst 130:156-162.
70. Kraus, W. and Nolze, G. (1996) POWDER CELL-a program for the representation and manipulation of crystal structures and calculation of the resulting X-ray powder patterns. J Appl Crystallogr 29:301-303.
71. Laetsch, T. and Downs, R. (2006) Software for identification and refinement of cell parameters from powder diffraction data of minerals using the RRUFF project and American Mineralogist Crystal Structure Databases [abstract P08-25]. In 19th General Meeting of the International Mineralogical Association, International Mineralogical Association, Kobe, Japan.
72. Lane, M.D., Bishop, J.L., Dyar, M.D., King, P.L., Parente, M., and Hyde, B.C. (2008) Mineralogy of the Paso Robles soils on Mars. Am Mineral 93:728-739.
73. Liermann, L.J., Hausrath, E.M., and Brantley., S.L. (2007) Assimilatory and dissimilatory processes of microorganisms affecting metals in the environment. J Anal At Spectrom 22: 867-877.
74. Liu, Z., Hu, J., Yang, H., Mao, H., and Hemley, R. (2002) Highpressure synchrotron X-ray diffraction and infra-red microspectroscopy: application to dense hydrous phases. J Phys Condens Matter 14:10641-10646.
75. Maurice, P.A., McKnight, D.M., Leff, L., Fulghum, J.E., and Gooseff, M. (2002) Direct observations of aluminosilicate weathering in the hyporheic zone of an Antarctic Dry Valley stream. Geochim Cosmochim Acta 66:1335-1347.
76. McCubbin, F.M. and Nekvasil, H. (2008) Maskelynite-hosted apatite in the Chassigny meteorite: insights into late-stage magmatic volatile evolution in martian magmas. Am Mineral 93:676-684.
77. McCubbin, F.M., Hauri, E.H., Elardo, S.M., Vander Kaaden, K.E., Wang, J., and Shearer, C.K., Jr. (2012) Hydrous melting of the martian mantle produced both depleted and enriched shergottites. Geology 40:683-686.
78. McSween, H.Y., Wyatt, M.B., Gellert, R., Bell, J.F., III, Morris, R.V., Herkenhoff, K.E., Crumpler, L.S., Milam, K.A., Stockstill, K.R., Tornabene, L.L., Arvidson, R.E., Bartlett, P., Blaney, D., Cabrol, N.A., Christensen, P.R., Clark, B.C., Crisp, J.A., Des Marais, D.J., Economou, T., Farmer, J.D., Farrand, W., Ghosh, A., Golombek, M., Gorevan, S., Greeley, R., Hamilton, V.E., Johnson, J.R., Joliff, B.L., Klingelhö fer, G., Knudson, A.T., McLennan, S., Ming, D., Moersch, J.E., Rieder, R., Ruff, S.W., Schrö der, C., de Souza, P.A., Jr., Squyres, S.W., Wänke, H., Wang, A., Yen, A., and Zipfel, J. (2006) Characterization and petrologic interpretation of olivine rich basalts at Gusev Crater, Mars. J Geophys Res 111, doi:10.1029/2005JE002477.
79. Ming, D.W., Mittlefehldt, D.W., Morris, R.V., Golden, D.C., Gellert, R., Yen, A., Clark, B.C., Squyres, S.W., Farrand, W.H., Ruff, S.W., Arvidson, R.E., Klingelhö fer, G., McSween, H.Y., Rodionov, D.S., Schrö der, C., de Souza, P.A., and Wang, A. (2006) Geochemical and mineralogical indicators for aqueous processes in the Columbia Hills of Gusev Crater, Mars. J Geophys Res 111, doi:10.1029/2005JE002560.
80. Moody, C.D., Edwards, H.G.M., and Worland, M.R. (2004) Raman spectroscopic studies of Antarctic endoliths and epiliths. In Proceedings of the Third European Workshop on Exo-Astrobiology, ESA SP-545, ESA Publications Division, Noordwijk, the Netherlands, pp 243-244.
81. Moore, P. (1973) Pegmatite phosphates: descriptive mineralogy and crystal chemistry. The Mineralogical Record 4:103-130.
82. Morris, R.V., Ming, D.W., Graff, T.G., Arvidson, R.E., Bell, J.F., Squyres, S.W., Mertzman, S.A., Gruener, J.E., Golden, D.C., Le, L., and Robinson, G.A. (2005) Hematite spherules in basaltic tephra altered under aqueous, acid-sulfate conditions on Mauna Kea volcano, Hawaii: possible clues for the occurrence of hematite-rich spherules in the Burns Formation at Meridiani Planum, Mars. Earth Planet Sci Lett 240:168-178.
83. Mouri, T. and Enami, M. (2008) Raman spectroscopic study of olivine-group minerals. Journal of Mineralogical and Petrological Sciences 103:100-104.
84. Nieto, F. (2002) Characterization of coexisting NH4-and K-micas in very low-grade metapelites. Am Mineral 87:205-216.
85. Nowicki, M.A. and Velbel, M.A. (2011) Preliminary quantification of a shape model for etch-pits formed during natural weathering of olivine. Appl Geochem 26:S112-S114.
86. Nugent, M.A., Brantley, S.L., Pantano, C.G., and Maurice, P.A. (1998) The influence of natural mineral coatings on feldspar weathering. Nature 395:588-591.
87. Oelkers, E.H. (2001) An experimental study of forsterite dissolution rates as a function of temperature and aqueous Mg and Si concentrations. Chem Geol 175:485-494.
88. Oelkers, E.H. and Gislason, S.R. (2001) The mechanism, rates and consequences of basaltic glass dissolution: I. An experimental study of the dissolution rates of basaltic glass as a function of aqueous Al, Si and oxalic acid concentration at 25-C and pH= 3 and 11. Geochim Cosmochim Acta 65:3671-3681.
89. Penel, G., Leroy, G., Rey, C., Sombret, B., Huvenne, J.P., and Bres, E. (1997) Infrared and Raman microspectrometry study of fluor-fluor-hydroxy and hydroxy-apatite powders. J Mater Sci Mater Med 8:271-276.
90. Pokrovsky, O.S. and Schott, J. (2000) Kinetics and mechanism of forsterite dissolution at 25 degrees C and pH from 1 to 12. Geochim Cosmochim Acta 64:3313-3325.
91. Prener, J.S. (1971) Nonstoichiometry in calcium chlorapatite. J Solid State Chem 3:49-55.
92. Rendón-Angeles, J.C., Yanagisawa, K., Ishizawa, N., and Oishi, S. (2000) Conversion of calcium fluorapatite into calcium hydroxyapatite under alkaline hydrothermal conditions. J Solid State Chem 151:65-72.
93. Rinaudo, C. and Gastaldi, D. (2003) Characterization of chrysotile, antigorite and lizardite by FT-Raman spectroscopy. Can Mineral 41:883-890.
94. Rosso, J.J. and Rimstidt, J.D. (2000) A high resolution study of forsterite dissolution rates. Geochim Cosmochim Acta 64:797-811.
95. Ruff, S.W., Christensen, P.R., Blaney, D.L., Farrand,W.H., Johnson, J.R.,Michalski, J.R.,Moersch, J.E.,Wright, S.P., and Squyres, S.W. (2006) The rocks of Gusev Crater as viewed by the Mini-TES instrument. J Geophys Res 111, 10.1029/2006JE002747.
96. Russell, N.C., Edwards, H.G.M., and Wynn-Williams, D.D. (1998) FT-Raman spectroscopic analysis of endolithic microbial communities from Beacon sandstone in Victoria Land, Antarctica. Antarct Sci 10:63-74.
97. Schiffman, P., Zierenberg, R., Marks, N., Bishop, J.L., and Dyar, M.D. (2006) Acid-fog deposition at Kilauea volcano: a possible mechanism for the formation of siliceous-sulfate rock coatings on Mars. Geology 34:921-924.
98. Schmidt, M.E., Ruff, S.W., McCoy, T.J., Farrand, W.H., Johnson, J.R., Gellert, R., Ming, D.W., Morris, R.V., Cabrol, N., Lewis, K.W., and Schroeder, C. (2008) Hydrothermal origin of halogens at Home Plate, Gusev Crater. J Geophys Res 113, doi:10.1029/2007JE003027.
99. Siegel, D.I. and Pfannkuch, H.O. (1984) Silicate mineral dissolution at pH 4 and near standard temperature and pressure. Geochim Cosmochim Acta 48:197-201.
100. Squyres, S.W., Arvidson, R.E., Ruff, S., Gellert, R., Morris, R.V., Ming, D.W., Crumpler, L., Farmer, J.D., Des Marais, D.J., Yen, A., McLennan, S.M., Calvin, W., Bell, J.F., III, Clark, B.C., Wang, A., McCoy, T.J., Schmidt, M.E., and de Souza, P.A., Jr. (2008) Detection of silica-rich deposits on Mars. Science 320:1063-1067.
101. Stockmann, G., Wolff-Boenisch, D., Gislason, S.R., and Oelkers, E.H. (2008) Dissolution of diopside and basaltic glass: the effect of carbonate coating. Mineral Mag 72:135-139.
102. Sudarsanan, K. and Young, R.A. (1978) Structural interactions of F, Cl and OH in apatites. Acta Crystallogr 34:1401-1407.
103. Thorn, C.E., Dixon, J.C., Darmody, R.G., and Allen, C.E. (2006) A 10-year record of the weathering rates of surficial pebbles in Karkevagge, Swedish Lapland. Catena 65:272-278.
104. Tosca, N.J., McLennan, S.M., Lindsley, D.H., and Schoonen, M.A.A. (2004) Acid-sulfate weathering of synthetic martian basalt: the acid fog model revisited. J Geophys Res 109, doi:10.1029/2003JE002218.
105. Van Herk, J., Pietersen, H.S., and Schuiling, R.D. (1989) Neutralization of industrial waste acids with olivine-the dissolution of forsteritic olivine at 40-70-C. Chem Geol 76:341-352.
106. Varnali, T., Edwards, H.G.M., and Hargreaves, M.D. (2009) Scytonemin: molecular structural studies of a key extremophilic biomarker for astrobiology. International Journal of Astrobiology 8:133-140.
107. Velbel, M.A. (1993) Formation of protective surface layers during silicate-mineral weathering under well-leached, oxidizing conditions. Am Mineral 78:405-414.
108. Velbel, M.A. (2009) Dissolution of olivine during natural weathering. Geochim Cosmochim Acta 73:6098-6113.
109. Velbel, M.A. and Ranck, J.M. (2008) Etch pits on naturally altered olivine from dunites of the Appalachian Blue Ridge Mountains, North Carolina, USA. Mineral Mag 72:145-148.
110. Villar, S.E.J., Edwards, H.G.M., and Worland, M.R. (2005) Comparative evaluation of Raman spectroscopy at different wavelengths for extremophile exemplars. Orig Life Evol Biosph 35:489-506.
111. Wilson, R., Monaghan, P., Bowden, S.A., Parnell, J., and Cooper, J.M. (2007) Surface-enhanced Raman signatures of pigmentation of cyanobacteria from within geological samples in a spectroscopic-microfluidic flow cell. Anal Chem 79:7036-7041.
112. Wogelius, R.A. and Walther, J.V. (1991) Olivine dissolution at 25-C: effects of pH, CO2, and organic acids. Geochim Cosmochim Acta 55:943-954.
113. Wogelius, R.A. and Walther, J.V. (1992) Olivine dissolution kinetics at near-surface conditions. Chem Geol 97:101-112.
114. Wolff-Boenisch, D., Gislason, S.R., Oelkers, E.H., and Putnis, C.V. (2004) The dissolution rates of natural glasses as a function of their composition at pH 4 and 10.6, and temperatures from 25 to 74-C. Geochim Cosmochim Acta 68:4843-4858.
115. Wynn-Williams, D.D. and Edwards, H.G.M. (2000) Antarctic ecosystems as models for extraterrestrial surface habitats. Planet Space Sci 48:1065-1075.
116. Wynn-Williams, D.D., Edwards, H.G.M., and Garcia-Pichel, F. (1999) Functional biomolecules of Antarctic stromatolitic and endolithic cyanobacterial communities. Eur J Phycol 34: 381-391.
117. Yen, A.S., Morris, R.V., Clark, B.C., Gellert, R., Knudson, A.T., Squyres, S., Mittlefehldt, D.W., Ming, D.W., Arvidson, R., McCoy, T., Schmidt, M., Hurowitz, J., Li, R., and Johnson, J.R. (2008) Hydrothermal processes at Gusev Crater: an evaluation of Paso Robles class soils. J Geophys Res 113, doi:10.1029/2007JE002978.