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mass independent fractionation

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A: Plot of Δ 36 S versus Δ 33 S for <b>mass</b>-<b>independent</b> <b>fractionation</b> (MIF) an...
in > Geology
Published: 01 May 2009
Figure 3. A: Plot of Δ 36 S versus Δ 33 S for mass-independent fractionation (MIF) and mass-dependent fractionation (MDF) data from Transvaal Supergroup. B: Enlargement of Δ 36 S versus Δ 33 S plot around origin. VCDT—Vienna Canyon Diablo troilite.
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The values of Δ 33 S, indicator of <b>mass</b> <b>independent</b> <b>fractionation</b> of sulfur...
Published: 01 December 2005
F ig . 1. The values of Δ 33 S, indicator of mass independent fractionation of sulfur in pyrite and barite during the past 4,000 m.y. The data were compiled by S. Ono from Farquhar et al. (2000 , 2002) , Hu et al. (2003) , Mojzsis et al. (2003) , and Ono et al. (2003) .
Journal Article
Journal: Elements
Published: 01 December 2009
Elements (2009) 5 (6): 353-357.
... mass-dependent (MDF) and mass-independent fractionation (MIF) (range of >6‰ for both), Hg isotopes are providing a valuable new tool for tracing this important toxin through the environment. MDF alone, which occurs during redox transformations, biological cycling, and volatilization of Hg, can...
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Journal Article
Journal: Geology
Published: 01 July 2013
Geology (2013) 41 (7): 791-794.
... of the Abitibi greenstone belt of the Superior craton in Canada was measured to test whether the results obtained from the Yilgarn craton apply to other Archean gold deposits. Sulfur analyses from sulfide from shale show mass-independent fractionation (MIF) with Δ 33 S as high as +1.8‰, whereas those from the 4...
FIGURES
Journal Article
Published: 01 January 2008
Reviews in Mineralogy and Geochemistry (2008) 68 (1): 187-218.
...Edward D. Young; Kyoshi Kuramoto; Rudolph A. Marcus; Hisayoshi Yurimoto; Stein B. Jacobsen Abstract In this chapter we compare and contrast chemical and photochemical pathways for mass-independent fractionation (MIF) of oxygen isotopes in the solar nebula. We begin by assessing the galactic...
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Journal Article
Journal: Economic Geology
Published: 01 March 2013
Economic Geology (2013) 108 (2): 365-377.
... obscures direct evidence for the mineralization process. Mass-independent fractionation of sulfur isotopes is a distinguishing feature of Archean sedimentary rocks, and reflects processes operating solely in the Archean surface environment. As a result, mass-independent fractionation of sulfur isotopes...
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Journal Article
Published: 01 June 2006
South African Journal of Geology (2006) 109 (1-2): 97-108.
...Shuhei Ono; Nicolas J. Beukes; Douglas Rumble; Marilyn L. Fogel Abstract Sulfur isotope mass-independent fractionation (S-MIF) is a unique geologic record of Archean atmospheric chemistry that provides important constraints on the evolution of the early Earth’s atmosphere and its impact on early...
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Journal Article
Journal: Economic Geology
Published: 01 September 2015
Economic Geology (2015) 110 (6): 1411-1423.
... by mantle sulfur but include a small amount of slightly negative mass-independent fractionation (MIF) anomalies, whereas sulfur from the pyrites in the sedimentary rocks has pronounced positive MIF, with ∆ 33 S values that lie between 0.19 and 6.20‰ (with one outlier at −1.62‰). The wall rocks...
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Journal Article
Journal: Geology
Published: 01 September 2006
Geology (2006) 34 (9): 761-764.
.... Here we use soil morphological characteristics, salt chemistry, and mass independent fractionation anomalies (Δ 17 O values) in dated paleosols to reconstruct a middle Miocene climatic transition from semiaridity to extreme hyperaridity in the Atacama Desert. Paleosols along the southeastern margin...
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Journal Article
Journal: Geology
Published: 19 May 2017
Geology (2017) 45 (8): 691-694.
... setting. Utilizing chemically conservative mass-independent fractionated sulfur (MIF-S) isotope signatures, we fingerprinted a major source of sulfur in these deposits. Contrary to previous studies, our data show that they display MIF-S isotope anomalies, with Δ 33 S values ranging from −1.18‰ to +2.04...
FIGURES
Journal Article
Journal: Geology
Published: 01 January 2017
Geology (2017) 45 (1): 55-58.
... Hg values are consistent with normal marine conditions but exhibit negative shifts coincident with increased Hg concentrations. Hg isotope mass-independent fractionation (Δ 199 Hg) trends are consistent with volcanic input in deep-water marine environments. In contrast, nearshore environments have Δ...
Series: Reviews in Economic Geology
Published: 01 January 2011
DOI: 10.5382/Rev.17.05
EISBN: 9781629490243
... of mass-independent fractionation of sulfur isotopes in the Pahtajärvi sulfides. T able 1. Chemical Composition of Narrow Ultramafic Dike Cutting Pillow Lavas of the Kolosjoki Volcanic Formation (1) Compared with Average Compositions of Ultramafic Rock Types from the Pahtajärvi Feeder Dike (2–3...
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Journal Article
Published: 01 January 2004
Reviews in Mineralogy and Geochemistry (2004) 55 (1): 289-317.
... nuclide 53 Mn, in meteorites ( Birck and Allegre 1988 ; Lee and Tera 1986 ; Shukolyukov and Lugmair 1998 ). However, this method measures only variations in radiogenic 53 Cr relative to the other isotopes. It removes the effects of mass-dependent isotope fractionation by normalizing measured 53 Cr...
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Journal Article
Published: 01 January 2001
Reviews in Mineralogy and Geochemistry (2001) 43 (1): 225-277.
... the subscripts na , Prot, Sacc, and Lip respectively refer to nucleic acids and related materials such as nucleoside cofactors, proteins and amino acids, mono- and polysaccharides, and lipids of all kinds. The X C terms, which sum to 1.0, refer to mole fractions of carbon and the δ terms refer to mass...
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Journal Article
Journal: Geophysics
Published: 20 May 2010
Geophysics (2010) 75 (3): N51-N63.
... processes: irreversible plastic yielding and formation of radial microfractures around microscopic cavities. Small-amplitude waves propagating through the rocks prestressed at their yield point would cause nonelastic strain to avoid building local stresses above the yield limit and attenuate some fraction...
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Journal Article
Journal: AAPG Bulletin
Published: 01 August 2017
AAPG Bulletin (2017) 101 (8): 1263-1275.
... the overall methane δ 13 C change through production was proposed to relate to the effect of adsorption amount on methane mass transport ( Xia and Tang, 2012 ). Specifically, when TOC increased and/or porosity decreased, the adsorption quantity relative to initial partial pressure increased, which might...
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Journal Article
Journal: Geology
Published: 01 December 2004
Geology (2004) 32 (12): 1017-1020.
.... The volume percentage of CO 2 (mole fraction) in the atmosphere remains almost constant with increasing elevation ( Gale, 1972 ). The partial pressure (i.e., mass per volume) of CO 2 decreases with decreasing barometric pressure [ pp ( z ) in pascals]: where m air is the molecular weight of air...
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Journal Article
Published: 01 October 2003
American Mineralogist (2003) 88 (10): 1514-1521.
...Daniel E. Kile; D.D. Eberl Abstract Crystal growth experiments were conducted using potassium alum and calcite crystals in aqueous solution under both non-stirred and stirred conditions to elucidate the mechanism for size-dependent (proportionate) and size-independent (constant) crystal growth...
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Journal Article
Published: 01 November 2010
Vadose Zone Journal (2010) 9 (4): 1025-1033.
... short of the available energy by 20 to 30%. As the causes for the energy imbalance are still under discussion, it is currently not clear how the energy balance should be closed. The objective of this study was to use independent measurements of evapotranspiration (ET) for empirically devising how...
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Journal Article
Published: 01 February 2004
American Mineralogist (2004) 89 (2-3): 432-437.
.... Recently Stimpfl et al. (1999) reconsidered the Fe-Mg site-occupancy data collected by XRD methods on the heat-treated Opx and concluded, contrary to most previous studies (e.g., Yang and Ghose 1994 ; Kroll et al. 1994 ), that the intracrystalline K d values are independent of the Opx composition...
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