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

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. Cl imaging shows no visible banding or …

(2004) at the assigned age, t. 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. 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. 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.

176hf 177hf

Hf from critical mid-ocean ridge basalts shows that 176Hf/177Hf does indeed have a greater variability than 143Nd/144Nd and 87Sr/86Sr in the depleted mantle. 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). 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 zircons ranged between 0.0005-0.001. 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).

Nov 28, 2016 8, 176Hf/177Hf = 0.282872 ± 30, εHf (present) = +3.1 ± 1.0. All of these values are within error of the accepted values (Fisher et al., 2014a and.

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.

the Hf isotope measurements were verified by repeated analyses of reference zircon GJ-1 and Temora, which yielded a 176Hf/177Hf of 0.282008 ± 0.000019 ( 2

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 Request PDF | Coupled Trace Element and Isotope Variations in Oceanic Basalts: Recycling Re-examined | In 1982 Hofmann and White (Nature, 295, p.363).

569-552 Ma) 176Hf/177Hf allowed to constrain the crystallization age (t) of the protolith. Trace elements in zircon do not show systematic variations no straightforward link to processes. 176Hf/177Hf in the rims are diﬀerent than in the cores in (t) C-833-A suggesting contribution of a Hf-enriched melt/ﬂuid. In sample C-838-A, 176Hf/177Hf suggests (t) 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. The martian meteorite Northwest Africa (NWA) 10169 is classified as a new member of the geochemically enriched poikilitic shergottites, based on mineral composition, Lu-Hf isotope systematics, and rare earth element (REE) composition. Akin to other poikilitic shergottites, it shows a similar bimodal texture to other enriched and intermediate poikilitic shergottites.
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the 93 Ma zircon protolith age (Liati. submarine lavas from Northern Kerguelen Plateau, is between a depleted component (i.e., relatively low 87Sr/86Sr with high 143Nd/144Nd and 176Hf/ 177Hf), vide reasonable solutions for the 208Pb/204Pb, 143Nd/144Nd, 176Hf/177Hf, and 3He/4He isotopic paradoxes or complexities of oceanic lavas. Although these They record precise U-Pb ages and initial 176Hf/177Hf isotope ratios providing important constraints on the age and nature of the metasomatic events occurring in Our 176Hf/177Hf results of both mafic and felsic geochemical reference standards agree with those reported by other authors.

176Hf/177Hf on Hf separates down to 1 µ of Hf with a Mar 16, 2012 (61) (176Hf/177Hf = 0.282785 and 176Lu/177Hf = 0.0336). Hf model ages were calculated using the reference line for the Hf isotope evolution analyses can be obtained, and the mean 176Lu/177Hf, 176Yb/177Yb and 176Hf/ 177Hf ratios are calculated. Reference zircon Mud Tank.
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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

(2000), who showed a spread in the data (n = 60) reference material for in situ Hf-isotope analysis (LAM- beyond 3σ of the typical internal precision, and this MC-ICPMS). The 176Hf/ 177Hf 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 143Nd/ 144Nd versus 176Hf/ 177Hf plot, Isotopic and trace element data imply a temporal change in magma sources and thermal conditions beneath the northern Fossa Magna, NE Japan arc from the Oligocene to the Pleistocene. Less radiogenic 176Hf/177Hf and 143Nd/144Nd, and high Zr/Hf characterize the Oligocene - Early Miocene volcanism in the northern Fossa Magna region.

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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).

Sample 2. Sample 3.

16 Nov 2015 model ages were calculated using new crust values of 176Hf/177Hf = 0.28315 and 176Lu/177Hf = 326. 0.03795 (Dhuime et al. 2011) and by

-7.7. 0.283253±3. 17.1. Loess, West China.

(2001) of 1.865 x 10-11.