Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-23T15:36:17.415Z Has data issue: false hasContentIssue false
  • English
  • Français

Reflectance Spectroscopy of Beidellites and Their Importance for Mars

Published online by Cambridge University Press:  01 January 2024

Janice L. Bishop ,
Will P. Gates ,
Heather D. Makarewicz ,
Nancy K. McKeown  and
Takahiro Hiroi
Janice L. Bishop*
Affiliation:
SETI Institute, 189 Bernardo Avenue, Mountain View, CA 94043, USA
Will P. Gates
Affiliation:
Monash University, Clayton, VIC 3800 Australia
Heather D. Makarewicz
Affiliation:
SETI Institute, 189 Bernardo Avenue, Mountain View, CA 94043, USA University of Kansas, Lawrence, KS 66045, USA
Nancy K. McKeown
Affiliation:
SETI Institute, 189 Bernardo Avenue, Mountain View, CA 94043, USA University of California at Santa Cruz, Santa Cruz, CA 95064, USA
Takahiro Hiroi
Affiliation:
Brown University, Providence, RI 02912, USA
*
* E-mail address of corresponding author: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Beidellites may exist on Mars and represent intermediate alteration products; their presence would indicate different alteration environments than previously identified because montmorillonite is a low-grade alteration mineral whereas beidellite is a higher-temperature alteration mineral, and often represents a step toward illite formation. The reflectance spectra of beidellites are under study to support their orbital detection on Mars, where spectral signatures of other Al-rich phyllosilicates have been observed. Reflectance spectra of ten Al-rich smectites are presented here which include pure beidellites and Al smectites having compositions between those of beidellite and montmorillonite, and emphasis is placed here on the OH combination bands near 4545 cm−1 (2.2 μm) as these vibrational features are commonly used in the identification of phyllosilicates on Mars. Shifts were observed in the Al2OH band centers, which occur near 4590 cm−1 (2.18 μm) in reflectance spectra of beidellite and near 4525 cm−1 (2.21 μm) in reflectance spectra of montmorillonite. These are compared with the Al2OH bending vibrations observed near 941–948 cm−1 (10.5–10.6 μm) for beidellite and near 918–926 cm−1 (10.8–10.9 μm) for montmorillonite. Although the octahedral site cation composition provides the greatest influence on the vibrational energies of the M2OH groups, the tetrahedral site cation composition also influences these vibrations. Shifts were observed in the Si-O-Al bending vibrations from 552 and 480 cm−1 (18.1 and 20.8 μm) in beidellite spectra to 544 and 475 cm−1 (18.4 and 21.0 μm) in montmorillonite spectra. Gaussian modeling of the 4545 cm−1 (2.2 μm) bands led to the discrimination of four overlapping bands in each of the ten Al smectite spectra examined in this study. Shifts in the band center and area of the primary spectral band are coordinated with substitution of Al for Si in the tetrahedral sheet. This is consistent with beidellites having a greater tetrahedral layer charge than montmorillonites. The observed spectral differences were sufficiently large that these Al-rich smectites can be differentiated in orbital data of Mars. A pure beidellite-type spectrum is observed in an isolated Al phyllosilicate-bearing outcrop in Libya Montes, a region where Fe-rich smectite is common but Al-rich smectite is rare. Beidellite-type reflectance spectra were also observed in one area of the Nili Fossae region. In contrast, a variety of Al phyllosilicates were found in the ancient rocks at Mawrth Vallis, including some smaller clay-bearing regions exhibiting spectral signatures more consistent with beidellite-like than montmorillonite-like chemistry.

Keywords

Al smectiteBeidelliteCRISMMarsMontmorilloniteOrbiterNili Fossae
Type
Article
Information
Clays and Clay Minerals , Volume 59 , Issue 4 , August 2011 , pp. 378 - 399
Copyright
Copyright © Clay Minerals Society 2011

References

Anderson, J.H. and Wickersheim, K.A., 1964 Near infrared characterization of water and hydroxyl groups on silica surfaces Surface Science 2 252–260.CrossRefGoogle Scholar
Battaglia, S. Leoni, L. and Sartori, F.A., 2006 A method for determining the CEC and chemical composition of clays via XRF Clay Minerals 41 717–725.CrossRefGoogle Scholar
Beaufort, D. Berger, G. Lacharpagne, J.C. and Meunier, A., 2001 An experimental alteration of montmorillonite to a di + trioctahedral smectite assemblage at 100 and 200°C Clay Minerals 36 211–225.CrossRefGoogle Scholar
Besson, G. and Drits, V.A., 1997 Refined relationships between chemical composition of dioctahedral fine-grained micaceous minerals and their infrared spectra within the OH stretching region Part I: Identification of the OH stretching bands. Clays and Clay Minerals 45 158–169.Google Scholar
Besson, G. and Drits, V.A., 1997 Refined relationships between chemical composition of dioctahedral fine-grained micaceous minerals and their infrared spectra within the OH stretching region Part II: The main factors affecting OH vibrations and quantitative analysis. Clays and Clay Minerals 45 170–183.Google Scholar
Bishop, J.L. Pieters, C.M. and Burns, R.G., 1993 Reflectance and Mössbauer spectroscopy of ferrihydrite-montmorillonite assemblages as Mars soil analog materials Geochimica et Cosmochimica Acta 57 4583–4595.CrossRefGoogle ScholarPubMed
Bishop, J.L. Pieters, C.M. and Edwards, J.O., 1994 Infrared spectroscopic analyses on the nature of water in montmorillonite Clays and Clay Minerals 42 701–715.CrossRefGoogle Scholar
Bishop, J.L. Madejová, J. Komadel, P. and Fröschl, H., 2002 The influence of structural Fe, Al and Mg on the infrared OH bands in spectra of dioctahedral smectites Clay Minerals 37 607–616.CrossRefGoogle Scholar
Bishop, J.L. Murad, E. and Dyar, M.D., 2002 The influence of octahedral and tetrahedral cation substitution on the structure of smectites and serpentines as observed through infrared spectroscopy Clay Minerals 37 617–628.CrossRefGoogle Scholar
Bishop, J.L. Lane, M.D. Dyar, M.D. and Brown, A.J., 2008 Reflectance and emission spectroscopy study of four groups of phyllosilicates: Smectites, kaolinite-serpentines, chlorites and micas Clay Minerals 43 35–54.CrossRefGoogle Scholar
Bishop, J.L. Noe Dobrea, E.Z. McKeown, N.K. Parente, M. Ehlmann, B.L. Michalski, J.R. Milliken, R.E. Poulet, F. Swayze, G.A. Mustard, J.F. Murchie, S.L. and Bibring, J.-P., 2008 Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars Science 321 830–833.CrossRefGoogle ScholarPubMed
Bishop, J.L. Makarewicz, H.D. Perry, K.A. McKeown, N.K. Parente, M. Tornabene, L.L. Swayze, G.A. Clark, R.N. Mustard, J.F. Murchie, S.L. and McEwen, A.S., 2010 Mineralogy of the Libya Montes and the Southern Isidis Planitia region: CRISM detection of clay, carbonate, olivine and pyroxene, and correlation with HiRISE imagery Lunar and Planetary Science Conference.Google Scholar
Bodine, M.W. Jr., 1987 CLAYFORM: A Fortran 77 computer program apportioning the constituents in the chemical analysis of a clay or other silicate mineral in a structural formula Computers and Geosciences 13 77–88.CrossRefGoogle Scholar
Brindley, G.W. and Brown, G., 1980 Crystal Structures of Clay Minerals and their X-ray Identification London Mineralogical Society 495.CrossRefGoogle Scholar
Chamley, H., 1989 Clay Sedimentology New York Springer-Verlag 623.CrossRefGoogle Scholar
Drief, A. and Nieto, F., 2000 Chemical composition of smectites formed in clastic sediments Implications for the smectite-illite transformation. Clay Minerals 35 665–678.CrossRefGoogle Scholar
Ehlmann, B.L., Mustard, J.F., Swayze, G.A., Clark, R.N., Bishop, J.L., Poulet, F., Marais, D.J.D., 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 MRO-CRISM: Geologic context near Nili Fossae and implications for aqueous alteration. Journal of Geophysical Research, 114,.CrossRefGoogle Scholar
Farmer, C.B. Davies, D.W. Holland, A.L. LaPorte, D.D. and Doms, P.E., 1977 Mars: Water vapor observations from the Viking orbiters Journal of Geophysical Research 82 4225–4248.CrossRefGoogle Scholar
Farmer, V.C. and Farmer, V.C., 1974 The layer silicates The Infrared Spectra of Minerals London The Mineralogical Society 331–363.CrossRefGoogle Scholar
Frank-Kamenetski, V.A. Kotelnikova, E.N. Kotov, N.V. and Starke, R., 1979 Influence of tetrahedral aluminium on the hydrothermal transformation of montmorillonite and beidellite to mixed-layer illite-montmorillonite and illite Kristall und Technik 14 303–311.CrossRefGoogle Scholar
Gates, W.P. and Kloprogge, J.T., 2005 Infrared spectroscopy and the chemistry of dioctahedral smectites The Application of Vibrational Spectroscopy to Clay Minerals and Layered Double Hydroxides Colorado, USA The Clay Minerals Society 125–168.Google Scholar
Gates, W.P. Komadel, P. Madejová, J. Bujdák, J. Stucki, J.W. and Kirkpatrick, R.J., 2000 Electronic and structural properties of reduced-charge montmorillonites Applied Clay Science 16 257–271.CrossRefGoogle Scholar
Gates, W.P. Slade, P.G. Lanson, B. and Manceau, A., 2002 Site occupancies by iron in nontronites Clays and Clay Minerals 50 223–239.CrossRefGoogle Scholar
Gharrabi, M. Velde, B. and Sagon, J.-P., 1998 The transformation of illite to muscovite in pelitic rocks: Constraints from X-ray diffraction Clays and Clay Minerals 46 79–88.CrossRefGoogle Scholar
Grauby, O. Petit, S. Decarreau, A. and Baronnet, A., 1993 The beidellite-saponite series: An experimental approach European Journal of Mineralogy 5 623–635.CrossRefGoogle Scholar
Grim, R.E., 1968 Clay Mineralogy New York McGraw-Hill Book Co. 596.Google Scholar
Guisseau, D. Mas, P.P. Beaufort, D. Girard, J.P. Inoue, A. Sanjuan, B. Petit, S. Lens, A. and Genter, A., 2007 Sigificance of the depth-related transition montmorillonite-beidellite in the Bouillante geothermal field (Guadeloupe, Lesser Antilles) American Mineralogist 92 1800–1813.CrossRefGoogle Scholar
Hiroi, T. and Pieters, C.M., 1998 Modified Gaussian deconvolution of reflectance spectra of Lunar soils Lunar and Planetary Science Conference.Google Scholar
Hunt, G.R. and Salisbury, J.W., 1970 Visible and near-infrared spectra of minerals and rocks: 1 Silicate minerals. Modern Geology 1 283–300.Google Scholar
Inoue, A. Meunier, A. and Beufort, D., 2004 Illite-smectite mixed-layer minerals in felsic volcaniclastic rocks from drill cores, Kakkonda, Japan Clays and Clay Minerals 52 66–84.CrossRefGoogle Scholar
Kloprogge, J.T., 2006 Spectroscopic studies of synthetic and natural beidellites: A review Applied Clay Science 31 165–179.CrossRefGoogle Scholar
Kloprogge, J.T. Komarneni, S. Yanagisawa, K. Frost, R.L. and Fry, R., 1998 Infrared study of some synthetic and natural beidellites Journal of Materials Science Letters 17 1853–1855.CrossRefGoogle Scholar
Komadel, P. Madejová, J. and Bujdák, J., 2005 Preparation and properties of reduced-charge smectites — A review Clays and Clay Mineral 53 313–334.CrossRefGoogle Scholar
Lanson, B. and Champion, D., 1991 The I/S-to-illite reaction in the late stafe diagenesis American Journal of Science 291 473–506.CrossRefGoogle Scholar
Lanson, B. and Besson, G., 1992 Characterization of the end of smectite-to-illite transformation: Decomposition of X-ray patterns Clays and Clay Minerals 40 40–52.CrossRefGoogle Scholar
Lantenlois, S. Muller, F. Bény, J.-M. Mahiaoui, J. and Champallier, R., 2008 Hydrothermal synthesis of beidellites: Characterization and study of the cis- and trans-vacant character Clays and Clay Minerals 56 39–48.CrossRefGoogle Scholar
Larsen, E.S. and Wherry, E.T., 1925 Beidellite, a new mineral name Journal of the Washington Academy of Sciences 15 465–466.Google Scholar
Loizeau, D., Mangold, N., Poulet, F., Bibring, J.-P., Gendrin, A., Ansan, V., Gomez, C., Gondet, B., Langevin, Y., Masson, P., and Neukum, G. (2007) Phyllosilicates in the Mawrth Vallis region of Mars. Journal of Geophysical Research, 112,.CrossRefGoogle Scholar
Loizeau, D. Mangold, N. Poulet, F. Ansan, V. Hauber, E. Bibring, J.P. Gondet, B. Langevin, Y. Masson, P. and Neukum, G., 2010 Stratigraphy in the Mawrth Vallis region through OMEGA, HRSC color imagery and DTM Icarus 205 396–418.CrossRefGoogle Scholar
Madejová, J. Komadel, P. and Cicel, B., 1994 Infrared study of octahedral site populations in smectites Clay Minerals 29 319–326.CrossRefGoogle Scholar
Madejová, J. Bujdak, J. Gates, W.P. and Komadel, P., 1996 Preparation and infrared spectroscopic characterization of reduced-charge montmorillonite with various Li contents Clay Minerals 31 233–241.CrossRefGoogle Scholar
Makarewicz, H.D. Parente, M. and Bishop, J.L., 2009 Deconvolution of VNIR Spectra Using Modified Gaussian Modeling (MGM) with Automatic Parameter Initialization (API) Applied to CRISM Hyperspectral Image and Signal Processing: Evolution in Remote Sensing.CrossRefGoogle Scholar
Malla, P.B. and Douglas, L.A., 1987 Problems in identification of montmorillonite and beidellite Clays and Clay Minerals 35 232–236.CrossRefGoogle Scholar
McKeown, N.K., Bishop, J.L., Noe Dobrea, E.Z., Ehlmann, B.L., Parente, M., Mustard, J.F., Murchie, S.L., Swayze, G.A., Bibring, J.-P., and Silver, E. (2009) Characterization of phyllosilicates observed in the central Mawrth Vallis region, Mars, their potential formational processes, and implications for past climate. Journal of Geophysical Research, 114,.CrossRefGoogle Scholar
McKeown, Nancy Bishop, Janice L. Cuadros, Javier Hillier, Stephen Amador, Elena Makarewicz, Heather D. Parente, Mario and Silver, Eli A., 2011 Interpretation of reflectance spectra of clay mineral-silica mixtures: implications for Martian clay mineralogy at Mawrth Vallis Clays and Clay Minerals 59 4 400–415.CrossRefGoogle Scholar
Meunier, A. and Velde, B., 2004 Illite: Origins, Evolution and Metamorphism Berlin Springer Verlag 286.CrossRefGoogle Scholar
Meunier, A. Lanson, B. and Beaufort, D., 2000 Vermiculitization of smectite interfaces and illite layer growth as a possible dual model for illite-smectite illitization in diagenetic environments: a synthesis Clay Minerals 35 573–586.CrossRefGoogle Scholar
Michalski, J.R. Kraft, M.D. Sharp, T.G. Williams, L.B. and Christensen, P.R., 2005 Emission spectroscopy and crystal chemistry of smectites: Mineralogical constraints on the high-silica Martian surface component observed by TES Icarus 174 161–171.CrossRefGoogle Scholar
Milliken, R.E., Swayze, G.A., Arvidson, R.L., Bishop, J.L., Clark, R., Ehlmann, B.L., Grotzinger, J., Morris, R., Murchie, S., Mustard, J., and Weitz, C. (2008a) Spectral evidence for sedimentary silica on Mars. Lunar and Planetary Science XXXIX, abstract #2025.Google Scholar
Milliken, R.E. Swayze, G.A. Arvidson, R.E. Bishop, J.L. Clark, R.N. Ehlmann, B.L. Green, R.O. Grotzinger, J. Morris, R.V. Murchie, S.L. Mustard, J.F. and Weitz, C.M., 2008 Opaline silica in young deposits on Mars Geology 36 847–850.CrossRefGoogle Scholar
Murchie, S., Arvidson, R., Bedini, P., Beisser, K., Bibring, J.-P., Bishop, J., Boldt, J., Cavender, P., Choo, T., Clancy, R.T., Darlington, E.H., Des Marais, D., Espiritu, R., Fort, D., Green, R., Guinness, E., Hayes, J., Hash, C., Heffernan, K., Hemmler, J., Heyler, G., Humm, D., Hutcheson, J., Izenberg, N., Lee, R., Lees, J., Lohr, D., Malaret, E., Martin, T., McGovern, J.A., McGuire, P., Morris, R., Mustard, J., Pelkey, S., Rhodes, E., Robinson, M., Roush, T., Schaefer, E., Seagrave, G., Seelos, F., Silvergate, P., Slavney, S., Smith, M., Shyong, W.-J., Strohbehn, K., Taylor, H., Thompson, P., Tossman, B., Wirzburger, M., and Wolff, M. (2007) Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on Mars Reconnaissance Orbiter (MRO). Journal of Geophysical Research, 112,.CrossRefGoogle Scholar
Murchie, S.L. Mustard, J. Ehlmann, B. Milliken, R.E. Bishop, J. McKeown, N. Noe Dobrea, E. Seelos, F. Buczkowski, D. Wiseman, S. Arvidson, R. Wray, J. Swayze, G. Clark, R. Des Marais, D. McEwen, A. and Bibring, J.-P., 2009 A synthesis of Martian aquous mineralogy after 1 Mars year of observations from the Mars Reconnaissance Orbiter Journal of Geophysical Research 114 E00D06.CrossRefGoogle Scholar
Mustard, J.F. Murchie, S.L. Pelkey, S.M. Ehlmann, B.L. Milliken, R.E. Grant, J.A. Bibring, J.-P. Poulet, F. Bishop, J.L. Noe Dobrea, E.Z. Roach, L.A. Seelos, F. Arvidson, R.E. Wiseman, S. Green, R. Hash, C. Humm, D. Malaret, E. McGovern, J.A. Seelos, K. Clancy, R.T. Clark, R.N. Des Marais, D. Izenberg, N. Knudson, A.T. Langevin, Y. Martin, T. McGuire, P. Morris, R.V. Robinson, M. Roush, T. Smith, M. Swayze, G.A. Taylor, H. Titus, T.N. and Wolff, M., 2008 Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument Nature 454 305–309.CrossRefGoogle ScholarPubMed
Noble, S.K., Pieters, C.M., Hiroi, T., and Taylor, L.A. (2006) Using the modified Gaussian model to extract quantitative data from lunar soils. Journal of Geophysical Research, 111,.CrossRefGoogle Scholar
Noe Dobrea, E.Z., Bishop, J.L., McKeown, N.K., Fu, R., Rossi, C.M., Michalski, J.R., Heinlein, C., Hanus, V., Poulet, F., Arvidson, R., Mustard, J.F., Ehlmann, B.L., Murchie, S., McEwen, A.S., Swayze, G., Bibring, J.-P., Malaret, J.F.E., and Hash, C. (2010) Mineralogy and stratigraphy of phyllosilicate-bearing and dark mantling units in the greater Mawrth Vallis: Constraints on geological origin. Journal of Geophysical Research, 115,.CrossRefGoogle Scholar
Norrish, K. and Hutton, J.T., 1967 An accurate X-ray spectrographic method for the analysis of a wide range of geological samples Geochimica et Cosmochimica Acta 33 431–453.CrossRefGoogle Scholar
Papanastassiou, D.A. and Wasserburg, G.J., 1974 Evidence for later formation and young metamorphism in the achondrite Nakhla Geophysical Research Letters 1 23–26.CrossRefGoogle Scholar
Papapanagiotou, P. Beaufort, D. Patrier, P. and Traineau, H., 2003 Clay mineralogy of the >0.2 m rock formation of the M1 drill hole of the geothermal field of Milos (Greece) Bulletin of the Geological Society of Greece 28 575–586.Google Scholar
Parente, M. Makarewicz, H.D. and Bishop, J.L., 2011 Decomposition of mineral absorption bands using nonlinear least squares curve fitting: Applications to Martian meteorites and CRISM data Planetary and Space Science 59 423–442.CrossRefGoogle Scholar
Petit, S. Decarreau, A. Martin, F. and Buchet, R., 2004 Refined relationship between the position of the fundamental OH stretching and the first overtones for clays Physics and Chemistry of Minerals 31 585–592.CrossRefGoogle Scholar
Post, J.L. and Noble, P.N., 1993 The near-infrared combination band frequencies of dioctahedral smectites, micas, and illites Clays and Clay Minerals 41 639–644.CrossRefGoogle Scholar
Post, J.L. and Borer, L., 2002 Physical properties of selected illites, beidellites and mixed-layer illite-beidellites from southwestern Idaho, and their infrared spectra Applied Clay Science 22 77–91.CrossRefGoogle Scholar
Poulet, F. Bibring, J.-P. Mustard, J.F. Gendrin, A. Mangold, N. Langevin, Y. Arvidson, R.E. Gondet, B. and Gomez, C., 2005 Phyllosilicates on Mars and implications for the early Mars history Nature 438 632.CrossRefGoogle Scholar
Robert, J.-L. and Kodama, H., 1988 Generalization of the correlations between hydroxyl-stretching wavenumbers and composition of micas in the system K2O-MgO-Al2O3-SiO2-H2O: A single model for trioctahedral and dioctahedral micas American Journal of Science 288A 196–212.Google Scholar
Russell, J.D. Fraser, A.R. and Wilson, M.J., 1994 Infrared methods Clay Mineralogy: Spectroscopic and Chemical Determinative Methods London Chapman & Hall 11–67.CrossRefGoogle Scholar
Saito, M.A. Sigman, D.M. and Morel, F.M.M., 2003 The bioinorganic chemistry of the ancient ocean: The coevolution of cyanobacterial metal requirements and biogeochemical cycles at the Archean-Proterozoic boundary? Inorganic Chimica Acta 356 308–318.CrossRefGoogle Scholar
Salisbury, J.W. Walter, L.S. Vergo, N. and D’Aria, D.M., 1991 Infrared (2.1–25 μm) Spectra of Minerals Baltimore, Maryland, USA Johns Hopkins University Press 267.Google Scholar
Salisbury, J.W. and Wald, A., 1992 The role of volume scattering in reducing spectral contrast of reststrahlen bands in spectra of powdered minerals Icarus 96 121–128.CrossRefGoogle Scholar
Salisbury, J.W., Pieters, C.M. and Englert, P.A.J., 1993 Mid-infrared spectroscopy: Laboratory data Remote Geochemical Analysis: Elemental and Mineralogical Composition Cambridge, UK Cambridge University Press 79–98.Google Scholar
Schultz, L.G., 1969 Lithium and Potassium absorption, dehydroxylation temperature, and structural water content of aluminous smectites Clays and Clay Minerals 17 115–149.CrossRefGoogle Scholar
Stubican, V. and Roy, R., 1961 Isomorphous substitution and infra-red spectra of the layer lattice silicates American Mineralogist 46 32–51.Google Scholar
Sunshine, J.M. and Pieters, C.M., 1993 Estimating modal abundances from the spectra of natural and laboratory pyroxene mixtures using the Modified Gaussian Model Journal of Geophysical Research 98 9075–9087.CrossRefGoogle Scholar
Sunshine, J.M. Pieters, C.M. and Pratt, S.F., 1990 Deconvolution of mineral absorption bands: An improved approach Journal of Geophysical Research 95 6955–6966.CrossRefGoogle Scholar
Velde, B., 1995 Origin and Mineralogy of Clays Berlin Springer-Verlag 334.CrossRefGoogle Scholar
Wilson, M.J., Schultz, L.G. van Olphen, H. and Mumpton, F.A., 1987 Soil smectites and related interstratified minerals: Recentd evelopments Proceedings of the International Clay Conference, Denver, 1985 Bloomington, Indiana, USA The Clay Minerals Society 167–173.Google Scholar
Wray, J. J. Ehlmann, B. L. Squyres, S. W. Mustard, J. F. and Kirk, R. L., 2008 Compositional stratigraphy of clay-bearing layered deposits at Mawrth Vallis, Mars Geophysical Research Letters 35 12 n/a-n/a.CrossRefGoogle Scholar
Yamada, H. Nakazawa, H. Yoshioka, K. and Fujita, T., 1991 Smectites in the montmorillonite-beidellite series Clay Minerals 26 359–369.CrossRefGoogle Scholar
Yamada, H. and Nakazawa, H., 1993 Isothermal treatments of regularly interstratified montmorillonite-beidellite at hydrothermal conditions Clays and Clay Minerals 41 726–730.CrossRefGoogle Scholar
Yang, K. Browne, P.L. Huntington, J.F. and Walshe, J.L., 2001 Characterising the hydrothermal alteration of the Broadlands-Ohaaki geothermal system, New Zealand, using short-wave infrared spectroscopy Journal of Volcanology and Geothermal Research 106 53–65.CrossRefGoogle Scholar