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.

Introduction: It is generally believed that the lower reproducibility to within 2ε (176Hf/177Hf=0.282284). 176 crust is mafic in composition, being formed primarily Lu/177Hf in …

The initial 176Hf/177Hf value (Hfi) in zircon is calculated using the measured 176Lu/177Hf, 176Hf/177Hf and apparent 207Pb/206Pb age and the 176Lu decay constant of Scherer et al. (2001) of 1.865 x 10-11. Model age calculations (TDM) are based on a depleted-mantle source with Hfi = 0.279718 and 176Lu/177Hf = 0.0384. The 176Hf/ 177Hf ratios for relatively radiogenic compositions (BCR-1, 2; BHVO-1, 2; RGM-1) were shifted systematically toward lower values by 100-150 ppm when a borosilicate primary column was used. Although systematic, the shift for felsic compositions was generally within analytical error, except for GSP-2, which has a very low Hf isotopic ratio, where the shift was to higher 176Hf/177. g-factors of rotational states in 176Hf and 180Hf were measured with the twelve detector IPAC-apparatus of our laboratory [1].

Early studies of Hf isotopes in subduction zones reached different conclusions regarding the mobility of high-field-strength elements during subduction-related processes. To test the behaviour of Hf during subduction, we have examined the young, intra-oceanic South Sandwich 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 … The initial 176Hf/177Hf value (Hfi) in zircon is calculated using the measured 176Lu/177Hf, 176Hf/177Hf and apparent 207Pb/206Pb age and the 176Lu decay constant of Scherer et al. (2001) of 1.865 x 10-11. Model age calculations (TDM) are based on a depleted-mantle source with Hfi = 0.279718 and 176Lu/177Hf = 0.0384.

176Hf/177Hf ratios are presented for oceanic volcanics representing both extremes of the range of mantle HfNdSr isotopic variation. Hf from critical mid-ocean ridgebasalts shows that 176Hf/177Hf does indeed have a greater variability than 143Nd/144Nd and 87Sr/86Sr in the depleted mantle. This extra variation is essentially of a random nature, and can perhaps be understood in terms of known Rb

A total of 59 Hf isotopic measurements (176Hf/177Hf = 0.282505 ± 0.000004, MSWD = 0.626; n = 331) was used as the primary RM for Hf isotopes (no correction was applied because measured calculate the hypothetical present-day 176Hf/177Hf of the zircons' parent rock based on an average crustal 176Lu/177Hf of 0.015 (Goodge and Vervoort,. 2006 ).

5. 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

Model age calculations (TDM) are based on a depleted-mantle source with Hfi = 0.279718 and 176Lu/177Hf = 0.0384. The 176Hf/ 177Hf ratios for relatively radiogenic compositions (BCR-1, 2; BHVO-1, 2; RGM-1) were shifted systematically toward lower values by 100-150 ppm when a borosilicate primary column was used. Although systematic, the shift for felsic compositions was generally within analytical error, except for GSP-2, which has a very low Hf isotopic ratio, where the shift was to higher 176Hf/177. g-factors of rotational states in 176Hf and 180Hf were measured with the twelve detector IPAC-apparatus of our laboratory [1]. The natural radioactivity 3.78 · 1010y 176Lu and the 5.5 h isomer 180mHf (2002) Andres et al. Geochemistry, Geophysics, Geosystems. Using high-precision multiple collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), 176Hf/177Hf was measured in 64 mid-ocean ridge basalts (MORB) from the Mid-Atlantic Ridge (MAR) between 40°S and 55°S and in one basalt from Both domains have higher initial 176Hf/177Hf values compared to relict cores and display REE patterns typical of zircon that grew contemporaneously with peritectic Grt1 through biotite-absent fluid partial melting.

The long-favored paradigm for the development of continental crust is one of progressive growth beginning at approximately 4 billion years ago (Ga). 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 (dev … Hafnium 176Hf to 177Hf isotope ratio analysis can provide insight into the different geological events and processes that a mineral underwent during its formation/metamorphosis; 176Hf/177Hf ratios No correlation between 176Hf/177Hf and Lu/Hf ratio is observed, suggesting no detectable inhomogeneity in the Hf isotopic ratios due to Lu decay. These results indicate FC-1 zircons that are 3 degrees magnetic or less are isotopically homogeneous with respect to Hf regardless of color or shape.
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used were 176Lu/177Hf = 0.0336 and 176Hf/177Hf = 0.282785 (Bouvier et al., 2008). For the depleted mantle reference curve, the straight-line model of Griffin High Sensitivity, 176Hf/177Hf, Jet Interface. Goal. This application note demonstrates that high precision. 176Hf/177Hf isotope ratios can now be obtained from.

176Hf/177Hf is positively correlated with 143Nd/144Nd, and negatively correlated with 87Sr/86Sr and 206Pb/204Pb.
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The data display a good correlation between Lu/Hf and 176Hf/177Hf (Fig. 1), and all results are consistent with a 4.55 Gy reference line. This shows that the

In general, proportional variations of 176Hf 177Hf exceed those of 143Nd l44Nd by factors of 1.5-3 in terrestrial and lunar materials. The SLC diopsides display a large range in 176Hf/ 177Hf, at near constant 143Nd/ 144Nd, and all lie to the high 176Hf/ 177Hf side of the MORB-0113 field (Fig. 2).

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A west-to-east geologic transect across the Peninsular Ranges batholith, San Diego County, California: Zircon 176Hf/177Hf evidence for the mixing of crustal- and

176Yb/177Hf ± 2 s.e. 176Lu/177Hf ± 2 s.e. Total Hf (V) Age (Ma) 176Hf/177Hf (t)1 2017-05-08 (2002) Andres et al. Geochemistry, Geophysics, Geosystems. Using high-precision multiple collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), 176Hf/177Hf was measured in 64 mid-ocean ridge basalts (MORB) from the Mid-Atlantic Ridge … Two of the granodiorite samples have suprachondritic 176Hf/177Hf ratios (avg. 0.28106 and 0.28107 at 2663 and 2651 Ma respectively) and nearly chondritic εHf values (avg.