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SmNd isotopic systematics of a gabbro-eclogite transition
Lithos, 1986Abstract SmNd isotopic systems have been studied in: (1) a sequence of coronitic olivine gabbros showing different degrees of transition to eclogite; (2) coronitic leuco-gabbro norite; and (3) country-rock eclogite, all from the Nordoyane-Brattvag area, western Norway. Isochrons defined by combinations of whole-rock samples and relict igneous phases
Mai Britt E. Mørk, Euan W. Mearns
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Sm-Nd isotopic evolution of chondrites and achondrites, II
Earth and Planetary Science Letters, 1984The ^(147)Sm-^(143)Nd and ^(146)Sm-^(142)Nd isotope systematics have been investigated in five chondrites and the achondrites Moama and Angra dos Reis (ADOR). The new chondrite data and those we have reported before are all consistent with our previously reported reference values for CHUR (“chondritic uniform reservoir”) of (^(143)Nd/^(144)Nd)_(CHUR)^0
Jacobsen, S. B., Wasserburg, G. J.
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Diffusion of Sm‐Nd in Scheelite and its Significance to Isotopic Dating and Tracing
Acta Geologica Sinica - English Edition, 2023AbstractAs the principal ore mineral in various tungsten (‐gold) deposits, scheelite (CaWO4) plays an important role in directly dating the timing of ore formation, and in tracing associated material sources through the study of its Sm‐Nd geochronology and Nd isotopic characteristics.
Dongliang ZHANG +4 more
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Isotopic evidence for chondritic Lu/Hf and Sm/Nd of the Moon
Earth and Planetary Science Letters, 2013Abstract Refractory lithophile elements are generally considered to occur in chondritic relative abundances in terrestrial planets. This assumption forms the basis for using isotope systems such as 176Lu–176Hf and 146, 147Sm–142, 143Nd as tracers of planetary evolution.
Sprung Peter +2 more
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Do supercontinents introvert or extrovert?: Sm-Nd isotope evidence
Geology, 2003In recent years, two end-member models for the formation of supercontinents have emerged. In the classical Wilson cycle, oceanic crust generated during supercontinent breakup (the interior ocean) is consumed during subsequent amalgamation so that the supercontinent turns “inside in” (introversion).
J. Brendan Murphy, R. Damian Nance
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Sm-Nd isotopic study of garnets and their metamorphic host rocks
Transactions of the Royal Society of Edinburgh: Earth Sciences, 1980ABSTRACTIn this feasibility study, Sm/Nd and 143Nd/144Nd ratios have been determined on garnets and coexisting mineral and whole-rock phases from a selection of amphibolite facies rocks, granulite facies rocks and an eclogite. In two micaceous schists and an eclogite the distribution coefficient of the Sm/Nd ratio in garnet relative to other phases is ...
O. van Breemen, C. J. Hawkesworth
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The theoretical effect of metasomatism on Sm-Nd isotopic systems
Geochimica et Cosmochimica Acta, 1990Abstract If Sm and Nd are mobilized during fluid-rock interaction, fractionation of the ratio between Sm and Nd in geological units may take place. The fractionation can be characterized by a fractionation factor F , which can attain any value between D Sm /D Nd and 1 /( D Sm /D Nd ) depending on the fluid/rock ratio ...
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Change of Sm-Nd isotope composition during weathering of till
Geochimica et Cosmochimica Acta, 2000Weathering of till in northern Sweden results in the formation of well-developed spodosols. The till is dominated by 1.9–1.8 Ga granitic material. The REE are among the elements most strongly depleted during weathering, and the loss of REE from the E-horizon decreases as the atomic number increases.
Björn Öhlander +3 more
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Sm—Nd isotopic age of Precambrian—Cambrian boundary in China
Geological Magazine, 1996AbstractBy the new method of Sm—Nd isotopic dating on phosphatic small skeletal fossils and collo-phanite minerals, the Zhongyicun Member of the earliest Cambrian Meishucun Stage at Meishucun in Yunnan, southern China, has been dated at 562.8 ± 7.9 Ma and 562.1 ± 5.7 Ma.
Yang Jie-Dong +3 more
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Lu-Hf and Sm-Nd isotope systems in zircon
Reviews in Mineralogy and Geochemistry, 2003As a significant carrier of uranium, thorium and the rare earth elements (REEs) at ppm level, and hafnium at the percent level, zircon hosts a remarkable number of long-lived radioactive isotopes and their stable decay products. These include 238U, 235U and 232Th which decay via intermediate steps to 206Pb, 207Pb and 208Pb, respectively, 176Lu which ...
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