Meteorites data sources

Data sources given in Haack and McCoy (2004). Values in parentheses are calculated initial liquid compositions for elements like Ir and Re with solid/liquid distribution coefficients that are far from unity, meteorite composition may be different from that of the initial liquid core. 

Figure 1 Na/Al versus FeO/MnO for achondrites. The FeO/MnO for acapulcoite-lodranite clan (ale), wino-naite-IAB-iron silicate inclusion clan (wic) and aubrites are for orthopyroxene. All other data are bulk rock values. Meteorite data are from sources listed in the text, while planet data are from McDonough and Sun (1995), Taylor (1982), and Wanke and Dreibus (1994).

Figure 5 Mare pyroclastic glasses tend to have far higher MgO, yet a similar range in Ti02, compared to crystalline mare basalts. For basalts, plotted data are averages of many literature analyses for basalt types (Table 2), except for lunar meteorites, which are individual rocks (shown with smaller filled squares). Other data sources are as cited by Arai and Warren (1999), i.e., primarily the compilation of Taylor et al. (1991) updated from Arai and Warren (1999) by adding lunar meteorites Dhofar 287 and NWA032 (but not the cumulate NWA773, 26 wt.% MgO, excluded because its composition is presumably unrepresentative of its magma type).

Figure 9 Covariation of CaO and AI2O3 in off-craton and on-craton xenoliths. Data sources in Table 6. Shown for reference are various estimates for primitive upper mantle (polygons) and the ratio in chondritic meteorites.

The r-nuclide content of the solar system. Since [29], the bulk SoS content of r-nuclides has been a key source of information. Uncertainties unfortunately still affect a variety of SoS r-nuclide abundances, which weakens to some extent their constraining virtues on r-process models. These uncertainties stem from various origins, including meteoritic data or, more importantly, models for the SoS s-process content, from which r-abundances are traditionally derived. They need to be kept in mind in particular when interpreting spectroscopic data [see (2) below]. It is difficult to see how this situation can be improved in a decisive way. Isotopic anomalies involving some r-nuclides have been identified in meteorites. They do not bring much useful information on the identification of the site and characteristics of the r-process. 

Fig. 1. The decreasing element concentration ratio of CM- over Cl chondrites indicates volatility related fractionations in CM meteorites and makes them of limited use as an abundance standard. The different symbol shapes indicate the principal mineral host phase for the elements (circle lithophile elements in silicate and oxides box siderophile elements in metal alloy chalcophile sulfides triangle halogen). Data sources for CM chondrites [21] plus updates Cl chondrites [17]...

The selected concentrations for the Orgueil meteorite, considered as most representative for the Cl chondrites, are listed in Table 2 details about the data sources are in LPG09. Concentrations are given as parts per million (ppm) by mass (10,000 ppm = 1 mass%). Corresponding atomic abundances normalized to 106 Si atoms (the cosmochemical abundance scale ) are listed as well. 

This chapter provides an overview of available noble gas data for solar system bodies apart from the Earth, Mars, and asteroids. Besides the Sun, the Moon, and the giant planets, we will also discuss data for the tenuous atmospheres of Mercury and the Moon, comets, interplanetary dust particles and elementary particles in the interplanetary medium and beyond. In addition, we summarize the scarce data base for the Venusian atmosphere. The extensive meteorite data from Mars and asteroidal sources are discussed in chapters in this volume by Ott (2002), Swindle (2002a,b) and Wieler (2002). Data from the Venusian and Martian atmospheres are discussed in more detail in chapters by Pepin and Porcelli (2002) and Swindle (2002b). Where appropriate, we will also present some data for other highly volatile elements such as H or N. 

Figure 8. Ne data from 4 lunar and 2 meteoritic samples containing solar noble gases. Gases were released by in vacuo etching, except for samples 10084 (stepwise heating) and 61501 (total fusion of aliquot samples previously etched off-line). Besides solar wind Ne (SW), all samples appear to contain a second solar component, labeled SEP. This is indicated e. g. by the many points on the mixing line SEP-GCR, where GCR represents the composition of Ne produced by Galactic Cosmic Rays. The Ne/ Ne ratios above the SW point in the first release fractions of 10084 (inset) indicate isotopic fractionation during gas extraction, which is not observed in the etch-experiments. Data sources listed in Wieler (1998). [Used by permission of Kluwer Academic Publishers, from Wieler (1998), Space Sci. Rev., Vol. 85, Fig. 1, p 304.]...

Figure 9. Exposure age distributions of HED meteorites (howardites, eucrites, diogenites) and aubrites or enstatite achondrites. The HED data are from the compilation by Welten et al. (1997), with only the (shielding corrected) Kr-Kr ages being displayed for the eucrites. Included are 4 new diogenite ages from Welten et al. (2001b). In addition, the -3 Myr age of the howardite Kapoeta has been added (Caffee and Nishiizumi 2001). For data sources of aubrites see text. Note the different abscissa scales between the lowermost panel and the others.

The second source of information about the early solar nebula comes from the primitive meteorites, which provide ages of 4.55 Ae. Although many classes of meteorites show elemental fractionations, the Type 1 carbonaceous chondrites (or Cl, where I = Ivuna, the type example of this class of meteorites) have a composition (excluding the volatile elements by which are meant in this context H, C, N, O and the rare gases) which is close to that of the relative abundances, normalised to Si, derived from the solar spectra. Lanthanide data are given in table 6. A comparison of the solar and meteoritic data is plotted in fig. 3 which shows the close correspondence between the two sets. This similarity is one of the pieces of evidence that we are dealing with the overall composition of the original solar... 

Percentage of meteorites seen to fall. Chondrites. Over 90% of meteorites that are observed to fall out of the sky are classified as chondrites, samples that are distinguished from terrestrial rocks in many ways (3). One of the most fundamental is age. Like most meteorites, chondrites have formation ages close to 4.55 Gyr. Elemental composition is also a property that distinguishes chondrites from all other terrestrial and extraterrestrial samples. Chondrites basically have undifferentiated elemental compositions for most nonvolatile elements and match solar abundances except for moderately volatile elements. The most compositionaHy primitive chondrites are members of the type 1 carbonaceous (Cl) class. The analyses of the small number of existing samples of this rare class most closely match estimates of solar compositions (5) and in fact are primary source solar or cosmic abundances data for the elements that cannot be accurately determined by analysis of lines in the solar spectmm (Table 2). Table 2. Solar System Abundances of the Elements ... 

Figure 9. Compilation of 5 Cu (%o) values in various copper ores (redrawn from Larson et al. 2003). Source of data Marechal et al. (1999), Zhu et al. (2000), Larsen et al. (in press) for ores, Marechal et al. (1999) and Zhu et al. (2000) for black smokers. Luck et al. (2003) for meteorites.

Agreement between the two sources of information is excellent. Moreover, laboratory analysis of meteorites can determine the isotopic composition of matter making up the Solar System, an invaluable piece of data for those intent on understanding the origin and evolution of atomic nuclei. 

Source of data Handbook of Geochemistry (K. H. Wedepohl, ed., Springer-Verlag, New York) Isotopes showing the Mossbauer effect isotope occurs in lunar samples and meteorites. 

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