To test this hypothesis, we measured initial 176Hf/177Hf values of 4.01- to 4.37-Ga detrital zircons from Jack Hills, Western Australia. epsilonHf (deviations of 176Hf/177Hf from bulk Earth in parts per 10(4)) values show large positive and negative deviations from those of the bulk Earth.
[JMC-475 250 ppb: 176Hf/177Hf=0.282161F16 (2 S.D.)] and Lu [JMC standard 50 ppb: 175Lu/176Lu=37.72F2 (2 S.D.)]. A total of 59 Hf isotopic measurements
176Hf/177Hf is the measured 176Hf/177Hf, corrected for fractionation and interfences. Shown with uncertainty expressed at 1-sigma. 6. 176Lu/177Hf is the intensity of 176Lu, calculated from the measured instensity of 175Lu and 176Lu/175Lu=0.02653 (from Patchett, 1983), compared to the measured intensity of 177Hf. Fractionation of Lu Calculates the initial 176Hf/177Hf values, the initial epsilon hafnium values, the model age using the measured 176Lu/177Hf value and the model age assuming the parental magma was produced from an average continental crust (176Lu/177Hf = 0.015) that originally was derived from the depleted mantle (Griffin, 2004).
Greater fractionation of Lu/Hf than Sm/Nd in planetary magmatic processes makes 176Hf 177Hf a powerful geochemical tracer. In general, proportional variations of 176Hf 177Hf exceed those of 143Nd l44Nd by factors of 1.5-3 in terrestrial and lunar materials. Lu-Hf studies therefore have a major contribution to 1997-04-01 Routine low-blank chemistry and 0.01-0.04% precision on the ratio 176Hf/177Hf allows study of Hf isotopic variations, generated by beta --decay of 176Lu, in volcanic rocks derived from the suboceanic mantle. Normalized to 176Hf/177Hf = 0.7325, 176Hf/177Hf ranges 0.2828-0.2835, based on 24 basalt samples. 176Hf/177Hf is positively correlated with 143Nd/144Nd, and negatively correlated with 87Sr 2020-07-23 2008-08-01 2004-12-01 Solution data from two laboratories (Amsterdam and M{\"u}nster) yield an average present day 176Hf/ 177Hf of 0.282000 ± 0.000005 (2σ weighted mean), which we recommend as a reference and nomination value for laser-ablation Hf isotope analyses.
0.282310±35 (2SD, n=19 ), 0.282028±34 (2SD, n=20), 0.282687±34 (2SD, n=20) and 0.282752±53 External reproducibility for 176Hf/177Hf was 5Ж 0Б000010 for an in-house standard and all Hf isotope data are reported relative to a value of 0Б28216 for 1700–2155 Ma) with more radiogenic initial Hf relative to Type I zircon (εHf = − 7.9 to +1.4, 176Hf/177Hf = 0.281427–0.281578); this type represents newly 176Yb+Lu interference correction on 176Hf/177Hf.
The lower concentration of 176Hf/177Hf is determined for magma from crustal reworking [19,45]. 3 Analytical techniques. 3.1 Zircon U–Pb dating and Hf isotope .
The measured isotopic ratios of 176Hf/177Hf were normalized to 179Hf/177Hf = 0.7325, using exponential correction for mass bias. In order to obtain accurate 176Hf/177Hf ratios, the isobaric interferences of 176Lu and 176Yb on 176Hf must be corrected. Normalized to 176Hf/177Hf = 0.7325, 176Hf/177Hf ranges 0.2828-0.2835, based on 24 basalt samples.
All samples contain a major component defined by 176Hf/177Hf =0.2828±0.00005, which appears in most of them to represent the earliest growth stage of zircon (Stage I). The granodiorite and the gabbro have the simplest patterns, consisting mainly of Stage I.
(2004) and the CHUR values of Bouvier et al. (2008). 176Hf/177Hf value of CHUR. calc_ab: Calculate slope and intercept calc_dens: Calculate 1D density of age data calc_dens_hist: Calculate scaled 1d density calc_dkw: Dvoretzky-Kiefer-Wolfowitz inequality Abstract The 176Hf/177Hf composition of inherited and magmatic zircon in the 538 Ma S-type Peninsula pluton (South Africa) has been determined at different scales. In the smallest rock samples investigated (<0.5 dm3), as well as within individual thin sections, magmatic zircon crystals exhibit the same wide range in εHf(538) as the pluton (8ε units). In addition, across a significant range 5.
1995-01-01
2002-05-01
The 176Lu-176Hf isotope method and its applications in earth sciences are discussed. Greater fractionation of Lu/Hf than Sm/Nd in planetary magmatic processes makes 176Hf 177Hf a powerful geochemical tracer. In general, proportional variations of 176Hf 177Hf exceed those of 143Nd l44Nd by factors of 1.5-3 in terrestrial and lunar materials. Lu-Hf studies therefore have a major contribution to
1997-04-01
Routine low-blank chemistry and 0.01-0.04% precision on the ratio 176Hf/177Hf allows study of Hf isotopic variations, generated by beta --decay of 176Lu, in volcanic rocks derived from the suboceanic mantle. Normalized to 176Hf/177Hf = 0.7325, 176Hf/177Hf ranges 0.2828-0.2835, based on 24 basalt samples. 176Hf/177Hf is positively correlated with 143Nd/144Nd, and negatively correlated with 87Sr
2020-07-23
2008-08-01
2004-12-01
Solution data from two laboratories (Amsterdam and M{\"u}nster) yield an average present day 176Hf/ 177Hf of 0.282000 ± 0.000005 (2σ weighted mean), which we recommend as a reference and nomination value for laser-ablation Hf isotope analyses.
Frogne taxameter
Cl imaging shows no visible banding or zonation for CL-active elements. The isotope 176Lu undergoes β- decay to 176Hf with a long half-life. From a plot of 176Hf/177Hf (y-axis) versus 176Lu/177Hf (x-axis) for a suite of cogenetic (=related) meteorites, Patchett & Tatsumoto (1980) obtained a 10-point isochrons with a slope of 0.0934 and an initial 176Hf/177Hf.
Naturally occurring Hafnium has 5 stable isotope - 176Hf, 177Hf, 178Hf, 179Hf, 180Hf. The 176Hf/177Hf composition of inherited and magmatic zircon in the 538 Ma S-type Peninsula pluton (South Africa) has been determined at different scales. In the smallest rock samples investigated (<0.5 dm3), as well as within individual thin
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The 176 Hf/ 177 Hf composition of inherited and magmatic zircon in the 538 Ma S-type Peninsula pluton (South Africa) has been determined at different scales.
76. February 11, 2009. εHf = ( 176 Hf /177 Hf )sample −(176 Hf /177 Hf )Chon. (176 Hf /177 Table 1. Zircon Hf–O isotopic data for the Langxian and the Nuri granitoids, southern Tibet. Sample #.