Lunar minerals

For cations most frequently encountered in terrestrial and lunar minerals, OMCT energies involving transition metal ions are calculated or observed to decrease in the order... 

Different evolutionary histories of other terrestrial planets have influenced the relative concentrations of the transition elements compared to their cosmic abundances, as suggested by geochemical data for surface rocks on the Moon, Mars and Venus (Appendix 1). Chemical analyses of lunar samples returned from the Apollo and Luna missions show that minerals and glasses occurring on the Moon contain high concentrations of Fe and Ti existing as oxidation states Fe(II), Ti(III) and Ti(IV). Some lunar minerals, notably olivine and opaque oxides, also contain significant amounts of Cr(H), Cr(III) and Mn(H). The lack of an atmosphere on the Moon simplifies interpretation of remote-sensed reflectance spectra of its surface. 

Figure 10.4 Diffuse reflectance spectra of powdered lunar minerals containing Fe2+ ions, (a) Plagioclase feldspar (b) orthopyroxene (c) calcic clinopyroxene and (d) olivine (courtesy of C. Pieters).

Vaughan, D. J. Bums, R. G. (1977) Electronic absorption spectra of lunar minerals. Phil. Trans. Royal Soc. Lond. A285,249-58. 

Papike J., Taylor L., and Simon S. (1991) Lunar minerals. In Lunar Sourcebook A User s Guide to the Moon (eds. G. Heiken, D. Vaniman, and B. M. French). Cambridge University Press, Cambridge, pp. 121-181. 

Figure 15 Noble-gas elemental ratios in IDPs compared with Cl meteorites and solar-wind (star) noble gas compositions are also plotted. Closed and open diamonds represent unheated IDPs and Zn-depleted IDPs, respectively. Square and circle represent lunar mineral separates (Singer et a/. 1977) and planetary bulk Cl chondrite (Jeffery and Anders, 1970), respectively (data courtesy of K. Kehm). See also Kehm et al. (2002).

Pepin R. O., Becker R. H., and Schlutter D. J. (1999) Irradiation records in regolith materials I. Isotopic compositions of solar-wind neon and argon in single lunar mineral grains. Geochim. Cosmochim. Acta 63, 2145—2162. 

In contrast to the occurrence of thallium as trace element, thallium minerals are very rare. Crookesite (from Skrikerum/ Sweden) is a mixture of the selenides of copper, thallium, and silver. Similar chemical compositions have been found in berze-lianite (Germany) and lorandite (Macedonia). Thallium has also been found in extraterrestrial material meteoric stones contain 0.001 to 0.2 tgg whilst lunar minerals contain 0.0006 to 0.0024 pgg (Urey 1952, Wedepohl 1974). 

The lunar soil is an ideal repository for implanted solar wind elements, as are certain gas-rich meteorites. Deuterium is depleted relative to the terrestrial standard in these materials, the D H ratio of <3 X 10 being consistent with the hypothesis that D is converted into He in the proto-Sun. Ion probe mass spectrometry has been used to study Mg, P, Ti, Cr and Fe which are present to enhanced levels in lunar minerals, indicating an exposure age of approximately 6 X 1Q4 y. The isotopic data indicate that the light isotopes of a number of elements have been preferentially lost from lunar material because of volatilization by micrometeorites or solar wind bombardment. There is some indication, from a study of Ne in gas-rich meteorites, of a large solar flare irradiation during the early history of the Solar System, perhaps related to the T-Tauri phase of the Sun. 

Yttrium occurs in nearly all of the rare-earth minerals. Analysis of lunar rock samples obtained during the Apollo missions show a relatively high yttrium content. 

The phosphorus chemistry occurring in interstellar matter and in the circum-stellar regions of the cosmos is not yet understood. We do, however, know that phosphorus compounds are present in meteorites, lunar rocks and Mars meteorites. Oddly enough, the element can be detected nearly everywhere, though only in low concentrations. Phosphate minerals, as well as the anions PO2 and PO3, have... 

The moon rocks brought back to earth are only a tiny sample of the moon s surface, but they are enough to show that some elements common on earth may be rare on the moon, and some that are rare here on earth may be common on the moon. So far, as on earth, oxygen and silicon seem to be the most common lunar elements. Early experiments have found more uranium and less potassium, more titanium and less sodium. Oxygen is strikingly absent from some minerals, but natural glass is far more common than it is on earth. The rare, noble gases are fairly abundant, trapped in little bubbles in the rocks. 

Among the oldest rocks on Earth are those on Isua, an island off the coast of Greenland they are 3.8 Gyr old, formed some 0.7 Gyr after accretion of the Earth. The rocks mark the beginning of the Archean period of geological time. The Isua rocks suggest that there was an extensive hydrosphere at this time, with erosion, transportation and deposition of minerals from water solution. The oldest lunar rocks, however, record an earlier high-temperature event - the Earth-Moon capture event. 

Stable isotope analysis of earth, moon and meteorite samples has provided important information concerning the origin of the solar system. Lunar samples returned to earth during the Apollo missions show 8170 and 8lsO enrichment patterns which are virtually identical to those of earth-bound rocks and minerals. On 3-isotope plots like those in Figs. 9.5 and 14.3, a uniform isotope reservoir is represented by a single... 

In Stable Isotope Geochemistry. Rev Miner Geochem 43 415 67 Beard BL, Johnson CM (1999) High-precision iron isotope measurements of terrestrial and lunar materials, Geochim Cosmochim Acta 63 1653-1660 Beard BL, Johnson C (2004) Fe isotope variations in the modem and ancient Earth and other planetary bodies. Rev Miner Geochem 55 319-357 Beard BL, Johnson CM, Cox L, Sun H, Nealson KH, Aguilar C (1999) Iron isotope biosphere. Science 285 1889-1892... 

Bums, R.G. (1994) Schwertmannite on Mars Deposition of this ferric oxyhydroxysulfate mineral in acidic saline meltwaters. Lunar Planetary Sd. 25, Part 1 203-204... 

Example 5.7. The oldest lunar rock known to date is a lunar highland anorthosite 60025. The data for different minerals in a single rock are shown in the table below (Carlson and Lugmair, 1988). Find the age. 

Seydoux-Guillaume AM, Wirth R, Nasdala L, Gottschalk M, Montel JM, Heinrich W (2002b) Phys Chem Minerals 29 240-253 Sharma S, Angel M, Ghosh M, Hubble H, Lucey P (2001) In Lunar and Planetary Science XXXII... 

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