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Evidence for inherited Sm?Nd isotopes in granitoid zircons
Contributions to Mineralogy and Petrology, 1992This study presents evidence to show that, in addition to preserving U−Pb isotope systematics, refractory zircons also preserve, at least in part, an inherited Sm−Nd isotope component. The zircons analyzed during this study were taken from the Strontian granitoid (NW Scotland). The inner intrusion of this composite pluton is known from a previous study
Rogers, G. +2 more
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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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Sm-Nd dating of Archaean basic and ultrabasic volcanics
Earth and Planetary Science Letters, 1977Abstract Sm-Nd data for ten greenstone belt volcanics from Rhodesia define an age of 2.64 ± 0.14AE , which is in agreement with other geochronological data and with observed field relationships. This age and the initial 143 Nd/ 144 Nd ratio of 0.50919 ± 0.00018 yield a time-integrated Sm/Nd ratio of 0.302 ± 0.009 in the mantle source region ...
P HAMILTON, R ONIONS, N EVENSEN
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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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RbSr and SmNd systematics of cherts and other siliceous deposits
Geochimica et Cosmochimica Acta, 1987We have analyzed a suite of marine and lacustrine cherts to determine the concentration of Rb, Sr, Sm and Nd and the isotopic composition of Sr and Nd. The samples ranged from Pliocene to Silurian in age and included nodular cherts in carbonates as well as bedded cherts.
Weis, D., Wasserburg, G. J.
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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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Sm/Nd constraints on the growth rate of continental crust
Tectonophysics, 1989Abstract The time constants are calculated which rule the evolution of Nd isotopes in a model Earth composed of the continental crust, a depleted upper mantle and a pristine lower mantle and in which the upper mantle is not constrained to grow or not to grow at the expense of the lower mantle. The growth rate of the continental crust is calculated to
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