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Isotopes and Isotope Ratios 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. 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 Solution multi-collector ICP-MS (MC-ICP-MS) measurements of Hf isotopes from chemically purified aliquots of GHR1 yield a mean 176Hf/177Hf of 0.283050 ± 17 (2s, n = 10), corresponding to a εHf0 of +9.3. Hafnium isotopic measurements from two LA-ICP-MS laboratories are in agreement with the solution MC-ICP-MS value. Home » ANU Research » ANU Scholarly Output » ANU Research Publications » Meteorite zircon constraints on the bulk Lu-Hf isotope composition and early differentiation of the Earth ANU Research » ANU Scholarly Output » ANU Research Publications » Meteorite zircon constraints on the bulk Lu-Hf isotope composition and early differentiation of the 1995-01-01 · If the high 176Hf/ 177Hf ratios evolve over a time scale simi lar to the age of the oceanic crust beneath Hawaii (- 100 Ma), then the protoliths probably origi nate in the lithosphere. If the high Hf isotope ratios evolve over hundreds of millions, or bil lions, of years, then the protoliths must derive from a deeper, less transient, part of the mantle.

Cl imaging shows no visible banding or … 4. 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. All 176Hf/177Hf ratios for standard and sample zircons were normalised to measurements of the Mud Tank reference zircon (average measured 176Hf/177Hf ratios during the course of two analytical sessions were 0.282493 ± 8, n = 14, and 0.282494 ± 8, n = 14, normalised to solution value of 0.282507) and compared with the FC1 secondary zircon standard (176Hf/177Hf normalised = 0.282167 ± 10 2014-09-16 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 … 2017-12-19 2001-12-01 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.

epsilonHf (dev … 2017-12-19 2001-12-01 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 Question: The Isotope 176Lu Undergoes β- Decay To 176Hf With A Long Half-life.

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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 … 1 calculated using the 176Lu decay constant of Soderlund et al. (2004) at the assigned age, t.

Deciphering the zircon Hf isotope systematics of Eoarchean

Request PDF | Coupled Trace Element and Isotope Variations in Oceanic Basalts: Recycling Re-examined | In 1982 Hofmann and White (Nature, 295, p.363). proposed that the enriched mantle components 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 Solution multi-collector ICP-MS (MC-ICP-MS) measurements of Hf isotopes from chemically purified aliquots of GHR1 yield a mean 176Hf/177Hf of 0.283050 ± 17 (2s, n = 10), corresponding to a εHf0 of +9.3.

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. Of the Hf isotopes of interest, 177Hf is free from direct isobaric overlap from any other element and does not typically suffer from polyatomic interference from other co-existing elements. However, the second Hf isotope used in the isotope ratio calculation, 176Hf, suffers isobaric overlap from 176Lu and Yb, as shown in Figure 1. 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. Resolution of 176Yb and 176Lu interferences on 176Hf to enable accurate 176Hf/177Hf isotope ratio analysis using an Agilent 8800 ICP-QQQ with MS/MS. PDF/ Found In: Application Notes ; Date : 27 Dec 2017; File Size : 1.24 MB Hafnium has five stable isotopes ( 176Hf, 177Hf, 178Hf, 179Hf, and 180Hf). List the total number of neutrons in each isotope.
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The 176Lu/ The 176Hf/177Hf ratio (0.282352 ± 22, n=14) of gem quality zircon used as in- house standard have been also characterized. As a geological application, we 176Hf/177Hf ratio during in-situ laser ablation MC-ICPMS analysis. It is shown For zircons, the obtained 176Hf/177Hf ratios are 0.282307±31 (2SD) for 91500 submarine lavas from Northern Kerguelen Plateau, is between a depleted component (i.e., relatively low 87Sr/86Sr with high 143Nd/144Nd and 176Hf/ 177Hf), mate' yielded a 176Lu/177Hf of 0.03976 and a 176Hf/177Hf of 0.283238.

epsilonHf (dev … 2017-12-19 2001-12-01 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 Question: 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 Ratio Of 0.27973.
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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 New 176Hf/177Hf measurements for 201 Ma Eastern North American tholeiites dominantly record a local petrogenetic history.

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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). 2017-12-19 · Introduction Hafnium 176Hf to 177Hf isotope ratio analysis can provide insight into the different geological events and processes that a mineral underwent 176Hf/177Hf ratios are presented for oceanic volcanics representing both extremes of the range of mantle HfNdSr isotopic variation.

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The range of Hf isotopes indicates mixing between crustal and mantle-derived magmas. We examine the relationships between zircon Hf isotopes and rock geochemistry. We argue that the crust and mantle derived magmas are silicic in composition. Question: 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 Ratio Of 0.27973. Request PDF | Coupled Trace Element and Isotope Variations in Oceanic Basalts: Recycling Re-examined | In 1982 Hofmann and White (Nature, 295, p.363).