Zinc chondrites

Virag A, Zinner E, Lewis RS, Tang M (1989) Isotopic compositions of H, C, and N in C8 diamonds from the Allende and Murray carbonaceous chondrites. Lunar Planet Sci XX 1158-1159 Volkening J, Papanastassiou DA (1989) Iron isotope anomalies. Astrophys J 347 L43-L46 Volkening J, Papanastassiou DA (1990) Zinc isotope anomalies. Astrophys J 358 L29-L32 Wadhwa M, Zinner EK, Crozaz G (1997) Manganese-chromium systematics in sulfides of unequilibrated enstatite chondrites. Meteorit Planet Sci 32 281-292... 

The bulk chemical composition of the dust, obtained by averaging the compositions of particles in numerous tracks (Fig. 12.11a) and impact crater residues (Fig. 12.11b), is chondritic for iron, silicon, titanium, chromium, manganese, nickel, germanium, and selenium, within the 2o confidence level (Flynn el al., 2006). Copper, zinc, and gallium are... 

Flynn, G. J. and Sutton, S. R. (1992) Trace elements in chondritic stratospheric particles zinc depletion as a possible indicator of atmospheric entry heating. Proceedings of the Lunar and Planetary Science Conference, 22, 171-184. 

In Figure 3, sodium, zinc, and sulfur are representative of the abundances of moderately volatile elements (Figure 2 and Table 2). Abundance variations reach a factor of 5 for sulfur and 10 for zinc. All three elements show excellent agreement of solar with Cl abundances, in contrast to other groups of chondritic meteorites, except for the enstatite chondrites, which reach the level of Cl abundances. However, enstatite chondrites... 

Many of the micron-sized interplanetary dust particles (IDPs) have approximately chondritic bulk composition (see Chapter 1.26 for details). Porous IDPs match the Cl composition better than nonporous (smooth) IDPs. On an average, IDPs show some enhancement of moderately volatile and volatile elements (see Palme, 2000). Arndt et al. (1996) found similar enrichments in their suite of 44 chondritic particles (average size 17.2 1.2 p.m). The elements chlorine, copper, zinc, gallium, selenium, and rubidium were enriched by factors of 2.2-2.7. In addition, these... 

Most chondritic IDPs have chondrite-like trace-element compositions (Arndt et al., 1996). Abundances in individual chondritic IDPs generally scatter from —0.3 X Cl to —3 X Cl and that enrichments are more common than depletions (Flynn and Sutton, 1992a,b,c). Volatile elements tend to be enriched relative to Cl meteorites (Ganapathy and Brownlee, 1979 Sutton, 1994). Enrichments of bromine measured in some IDPs probably reflect stratospheric contamination (Van der Stap et al., 1986 Elynn, 1994a Hynn et al., 1996), and zinc depletions probably reflect loss of... 

The concentrations of four typical moderately volatile elements—manganese, sodium, selenium, and zinc—in the various classes of chondritic meteorites are shown in Figure 12, where elements are normalized to magnesium and CI-chondrites. Again there is excellent agreement between solar abundances and Cl-meteorites. A characteristic feature of the chemistry of carbonaceous chondrites is the simultaneous depletion of sodium and manganese in all types of carbonaceous chondrites, except Cl. Ordinary and enstatite chondrites are not or only slightly... 

In Figure 13 the Earth s mantle seems to extend the trend of the moderately volatile elements to lower abundances, at least for sodium, manganese, and zinc (zinc behaves as a lithophile element in the Earth s mantle (see Dreibus and Palme, 1996)). The elements lithium, potassium, and rubidium which are not plotted here, show similar trends. The carbonaceous chondrite trend of iron is not extended to the Earth, as most of the iron of the Earth is in the core. The magnesium abundance of the Earth shows a slightly different trend. If the core had 5% silicon (previous section) and if that would be added to the bulk Earth silicon, then the bulk Mg/Si ratio of the Earth would be the same as that of carbonaceous chondrites (Eigure 10) and the silicon abundance of the Earth s mantle in Figure 13 would coincide with the magnesium abundance. 

Vanadium (element No. 23) is comparatively abundant in the universe. At 0.0001%, its cosmic abundance is comparable to that of copper and zinc. The cosmic abundance is, e.g., reflected in chondritic meteorites, which contain 220 atoms of the isotope in relation to 10 silicium atoms. Cosmic formation of vanadium is based on the a, y cascade up to Cr, followed by the reaction sequence ... 

Fan TW-M, Teh SJ, Hinton DE, Higashi RM (2002) Selenium biotransformations into proteinaceous forms by foodweb organisms of selenium-laden drainage waters in California. Aquatic Toxicology 57 65-84 Flynn GJ, Sutton SR (1992) Trace Elements in Chondritic Stratospheric Particles Zinc Depletion as a Possible Indicator of Atmospheric Entry Heating. Proc. Of Lunar and Planetary Science 22, Lunar and Planetary Institute, Houston, 171-184... 

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