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

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

176 crust is mafic in composition, being formed primarily Lu/177Hf in zircons ranged between 0.0005-0.001. New 176Hf/177Hf measurements for 201 Ma Eastern North American tholeiites dominantly record a local petrogenetic history. Their εHf ratios, corrected to an emplacement age of 201 Ma (-7.85 to +5.86), form a positive but shallowly sloped array slightly deviating from the terrestrial array on a εHf vs. εNd diagram. Some heterogeneity in 176Hf/177Hf was noted by Griffin We have used 91500 regularly since 1999 as a et al. (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.

176hf 177hf

Sample 3. Apparent older Lu-Hf age. Sample 4. Correct age. Correct initial 176Hf/177Hf.

176Yb/172Yb ratio to be Tank reference zircon gave 176Hf/177Hf ¼ 0·282510 Ж49. (2SD, n ¼ 817), The New England Batholith of eastern Australia: Evidence of silicic magma mixing from zircon 176Hf/177Hf ratios. S.E. Shaw, R.H. Flood, N.J. Pearson.

submarine lavas from Northern Kerguelen Plateau, is between a depleted component (i.e., relatively low 87Sr/86Sr with high 143Nd/144Nd and 176Hf/ 177Hf),

In the smallest rock samples investigated (<0.5 dm3), as well as within individual thin 5. 176Hf/177Hf is the measured 176Hf/177Hf, corrected for fractionation and interfences.

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

What is the average molar mass given these isotopes. (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 … 1 calculated using the 176Lu decay constant of Soderlund et al. (2004) at the assigned age, t.

Earth Planet. Sci. Lett., 129 (1–4) (1995), pp. 13-30. Article Download PDF View Record in Scopus Google 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.
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isochrons, the 2σ uncertainties on 176Hf/177Hf are estimated using the method of bizzarro et al.

83.27. The lower concentration of 176Hf/177Hf is determined for magma from crustal reworking [19,45].
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New 176Hf/177Hf measurements for 201 Ma Eastern North American tholeiites dominantly record a local petrogenetic history. Their εHf ratios, corrected to an emplacement age of 201 Ma (-7.85 to +5.86), form a positive but shallowly sloped array slightly deviating from the terrestrial array on a εHf vs. εNd diagram.

Lecture 8.

18 Jun 2010 176Lu/177Hf. 176. Hf/. 177. Hf. Sample 1. Sample 2. Sample 3. Apparent older Lu-Hf age. Sample 4. Correct age. Correct initial 176Hf/177Hf.

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.

Table 1. 177Hf = 0.0388, 176Hf/177Hf = 0.2832568.