176Hf/177Hf ± 2 s.e. 178Hf/177Hf ± 2 s.e. 176Yb/177Hf ± 2 s.e. 176Lu/177Hf ± 2 s.e. Total Hf (V) Age (Ma) 176Hf/177Hf (t)1

The 176Hf/177Hf ratio shows a wide range, from 0.2811 to 0.2858 (εHf = -55 to +110); much of this range is found within single samples and even within single grains. We suggest that the MARID rutiles initially resulted from the interaction of an asthenospheric melt with ancient depleted harzburgitic mantle with low 176Hf/177Hf ratios (<0.2812) and Lu/Hf ratios of ∼0.04, that dominated their

Hf isotopic analyses of all 6 fractions yielded very consistent results with the average 176Hf/177Hf=0.282174 ± 12 (2 S.D.), relative to JMC-475 176Hf/177Hf=0.282162 ± 5 (2 S.D.). Laser ablation analyses of individual grains from the six fractions yielded similar results, with an average 176Hf/177Hf=0.282174 ± 15 (2 S.D.). Solution data from two laboratories (Amsterdam and Münster) yield an average present day 176 Hf/ 177 Hf of 0.282000 ± 0.000005 (2σ weighted mean), which we recommend as a reference and nomination value for laser-ablation Hf isotope analyses. Cl imaging shows no visible banding or zonation for CL-active elements. 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 Ratio Of 0.27973. The Age Of The Meteorites Is Known To Be 4550 This problem has been solved!

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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 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.

The 176 Hf/ 177 Hf ratio of the Solar System material 4.56 Ga ago was 0.279742 ± 29. Because the mantle array lies above the Bulk Silicate Earth in a 143 Nd/ 144 Nd versus 176 Hf/ 177 Hf plot, no terrestrial basalt seems to have formed from a primitive undifferentiated mantle, thereby casting doubt on the significance of high 3 He/ 4 He ratios.

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 ). used were 176Lu/177Hf = 0.0336 and 176Hf/177Hf = 0.282785 (Bouvier et al., 2008).

Purification of Hf in silicate materials using extraction chromatographic resin, and its application to precise determination of 176 Hf/ 177 Hf by MC-ICP-MS with 179 Hf spike.

176Hf/177Hf ratio is a combination of two deter- minations. Two loading methods were primarily used, one following the method of Corfu and Nobel [25], which uses a single Re filament with an Ir-C slurry, and the other following the method of Patchett and Tatsumoto [22 The similarity of the Lu–Hf and Sm–Nd isotope system during most mantle differentiation processes makes the combination of 176Hf/177Hf and 143Nd/144Nd a very sensitive indicator of a select number of processes. This paper present new Hf-isotope data for a large number of ocean islands and examines the Hf–Nd–Pb isotope relations of oceanic volcanics.

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. 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). 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 Hafnium 176Hf/177Hf isotope ratio variations in marine records are thought to reflect changes in continental weathering through time, but the behavior of Hf in rivers, and during weathering, is not well understood. Here, we present 176Hf/177Hf data for rivers, bedrock, soils, and leaching experiments for the Moselle basin, Vosges, France. 176Hf/177Hf isotopes provide information about the behaviour of so-called immobile elements in subduction environments.
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What is the average molar mass given these isotopes. Solution data from two laboratories (Amsterdam and Münster) yield an average present day 176 Hf/ 177 Hf of 0.282000 ± 0.000005 (2σ weighted mean), which we recommend as a reference and nomination value for laser-ablation Hf isotope analyses.

Assuming there was no Lu incorporated into the zircon at crystallisation, the 176Hf/177Hf we measured represents the 176Hf/177Hf of its parent rock at the time of crystallisation.
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resulting in poor ionization efficiencies for thermal ionization. Previous techniques were able to measure. 176Hf/177Hf on Hf separates down to 1 µ of Hf with a 

37.23. < 75 um. 0.512242±5. -7.7.

[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 

2017-03-08 · 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 Isotopes and Isotope Ratios The 176Hf/177Hf ratio of the in-house standard Reagent blanks for Hf and Nd determined by has been measured relative to 176Hf/177Hf / isotope dilution are all B/0.1 pg g 1 for both 0.2821609/10 (2 S.D., n /4) obtained for interna- elements. 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].

Two loading methods were primarily used, one following the method of Corfu and Nobel [25], which uses a single Re filament with Typical analytical uncertainties of ±0.005% in 176Hf/177Hf combined with a bulk 176Lu/177Hf ratio in metapelitic garnets of ~10 (±0.5% uncertainty) result in theoretical age uncertainties of only ±2 Myr and ±200 kyr for 400 and 30 Ma garnets respectively. 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 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.