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Geochemistry isotopic ratios

Merritt, D. A., Brand, W. A. and Hayes, J. M. (1994) Isotope ratio monitoring gas chromatography mass spectrometry methods for isotopic calibration. Organic Geochemistry 21, 573 583. [Pg.429]

Yang, H. and Huang, Y. (2003) Preservation of lipid hydrogen isotope ratios in Miocene lacustrine sediments and plant fossils at Clarkia, northern Idaho, USA. Organic Geochemistry 34, 413. [Pg.432]

Stern, B., Clelland, S.J., Nordby, C.C. and Urem-Kotsou, D. (2006). Bulk stable light isotopic ratios in archaeological birch bark tars. Applied Geochemistry 21 1668-1673. [Pg.269]

Grape, G., Price, T.D., Schroter, P., Sollner, F., Johnson, C.M. and Beard, B.L. (1997). Mobility of Bell Beaker people revealed by strontium isotope ratios of tooth and bone a study of southern Bavarian skeletal remains. Applied Geochemistry 12 517-525. [Pg.376]

Selected applications of isotope ratio monitoring technique in mass spectrometry to geochemistry, biology, medicine and other areas of science are described. It was shown that gas isotope ratio mass spectrometry has greatly increased our understanding of the biogeochemical cycles of C, N, S and H2O in natural and agricultural ecosystems. [Pg.151]

Once formed, the LNAPL is referred to as a pool that is really a continuous accumulation of LNAPL. Subpools are individual accumulations of relatively uniform free-product types based on geochemistry (API gravity, specific constituents, isotope ratios, etc.) that have coalesced, reflecting multiple-source accumulations with time. The LNAPL pool, once formed, also maintains a capillary fringe. The anticipated capillary rise of LNAPL can be calculated as follows ... [Pg.159]

Shortly after the development of the early mass spectrometers, Li isotopes were identified by Francis Aston (1932). Although mass spectrometric techniques are those most commonly applied to the measurement of isotope ratios in geochemistry, attempts to quantify Li isotopes have been made using non-mass based emission methods (e.g., atomic absorption Zaidel and Korennoi 1961 various nuclear methods Kaplan and Wilzbach 1954 Brown et al. 1978 ... [Pg.155]

SpivackAJ, Edmond JM (1986) Determination of boron isotope ratios by thermal ionization mass spectrometry of the dicesium metaborate cation. Anal Chem 58 31-35 Spivack AJ, Kastner M, Ransom B (2002) Elemental and isotopic chloride geochemistry and fluid flow in the Nankai Trough. Geophys Res Lett 29 1-4... [Pg.253]

Until only a few years ago, I would never have imagined that a volume on the stable isotope geochemistry of elements like Mg, Fe or Cu would be written. In fact, a comic book of blank pages entitled The Stable Isotope Geochemistry of Fluorine would have been a more likely prospect. In volume 16 of this series, published in 1986, I wrote Isotopic variations have been looked for but not found for heavy elements like Cu, Sn, and Fe.. .. Natural variations in isotopic ratios of terrestrial materials have been reportedfor other light elements like Mg and K, but such variations usually turn out to be laboratory artifacts. I am about ready to eat those words. [Pg.458]

The foundations of stable isotope geochemistry were laid in 1947 by Urey s classic paper on the thermodynamic properties of isotopic substances and by Nier s development of the ratio mass spectrometer. Before discussing details of the naturally occurring variations in stable isotope ratios, it is useful to describe some generalities that are pertinent to the field of non-radiogenic isotope geochemistry as a whole. [Pg.35]

T1 isotope ratios might be also used as a tracer in mantle geochemistry (Nielsen et al. 2006 2007). Since most geochemical reservoirs except Fe-Mn marine sediments and low temperature seawater altered basalts are more or less invariant in T1 isotope composition, admixing af small amounts of either of these two components into the mantle should induce small T1 isotope fractionations in mantle derived rocks. And indeed, evidence for the presence of Fe-Mn sediments in the mantle underneath Hawaii was presented by Nielsen et al. (2006). [Pg.92]

Chivas AR, Andrew AS, Sinha AK, O Neil JR (1982) Geochemistry of Phocene-Pleistocene oceanic arc plutonic complex, Guadalcanal. Nature 300 139-143 Chmeleff J, Horn 1, Steinhofel G, von Blanckenburg L (2008) In situ determination of predse stable Si isotope ratios by UV-femtosecond laser ablation high-resolution multi-coUector ICP-MS. Chem Geol 249 155-160... [Pg.236]

Knauth LP, Lowe DR (1978) Oxygen isotope geochemistry of cherts from the Onverwacht group (3,4 billion years), Transvaal, South Africa, with implications for secular variations in the isotopic composition of chert. Earth Planet Sci Lett 41 209-222 Knoll AH, Hayes JM, Kaufman AJ, Swett K, Lambert IB (1986) Secular variation in carbon isotope ratios from Upper Proterozoic successions of Svalbard and East Greenland. Nature 321 832-838... [Pg.253]

Rabinovich AL, Grinenko VA (1979) Sulfate sulfur isotope ratios for USSR river water. Geochemistry 16 No 2 68-79... [Pg.264]

Sharp ZD (1990) A laser-based microanalytical method for the in situ determination of oxygen isotope ratios of sUicates and oxides. Geochim Cosmochim Acta 54 1353-1357 Sharp ZD (1995) Oxygen isotope geochemistry of the Al2Si05 polymorphs. Am J Sci 295 1058-1076... [Pg.270]

Equation (5.7), rather than (5.6), is used in isotope geochemistry, because mass spectrometers can measure isotopic ratios (G/Gg) significantly more precise than the amount of an isotope (G). [Pg.75]

The highly precise measurement of isotope ratios has a long tradition in organic geochemistry. Nowadays, the elucidation of stable isotope distributions is highly desirable in view of fundamental studies in biochemistry, nutrition, drug research and also in the authenticity assessment of food ingredients. [Pg.394]

Applications of Isotope Ratio Measurements in Geochemistry and Geochronology... [Pg.246]


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See also in sourсe #XX -- [ Pg.76 , Pg.77 , Pg.87 , Pg.88 , Pg.94 ]




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