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New Nd magnetic phase in Sm/Nd superlattices
Journal of Magnetism and Magnetic Materials, 2004Magnetic phases and coherence have been investigated in a (001) Sm/Nd superlattice using Resonant X-ray magnetic scattering. The magnetic phases in Sm layers are similar to the ones evidenced in double hexagonal compact thick films. On the contrary, the magnetism in Nd layers exhibits strong differences with the bulk case, especially the occurrence of ...
S. Soriano +4 more
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1988
The Sm-Nd system is useful for determining crystallization ages of igneous and metamorphic rocks. It has proven especially valuable for dating mafic and ultramafic rocks that are, in general, difficult to date using other methods. The principles of Sm-Nd dating are identical to those of Rb-Sr dating, which have been discussed in detail elsewhere (e.g ...
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The Sm-Nd system is useful for determining crystallization ages of igneous and metamorphic rocks. It has proven especially valuable for dating mafic and ultramafic rocks that are, in general, difficult to date using other methods. The principles of Sm-Nd dating are identical to those of Rb-Sr dating, which have been discussed in detail elsewhere (e.g ...
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Sm-Nd crustal provinces in Antarctica
Doklady Earth Sciences, 2008Since the 1960s, the structure and age of the Antarctic crust has been the object of systematic study [1, 2, and others]. East Antarctica is an ancient platform, while the West Antarctica and Transantarctic Mountains are composed of different-age Phanerozoic fold systems.
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Sm-Nd and Rb-Sr isotopic systematics of ureilites
Geochimica et Cosmochimica Acta, 1991The present evaluation of Sm-Nd and Rb-Sr isotopic data for seven ureilites establishes their divisions into three groups on the bases of Sm-Nd isotopic systematics. The first group of ureilites is made up of whole-rock samples whose highly depleted assemblages indicate Sm-Nd model ages consistent with 4.55 Ga. The second group of whole-rock samples of
Cyrena Anne Goodrich +3 more
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Mineralogical Magazine, 1994
The application of the garnet Sm-Nd dating method to granulite facies metamorphic rocks has been brought into question by recent claims of a low closure temperature (c. 600~ for the SmNd isotopic system in garnet (Mezger et al., 1992, Burton et al., 1993). We present evidence for a more robust garnet memory under granulite facies conditions.
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The application of the garnet Sm-Nd dating method to granulite facies metamorphic rocks has been brought into question by recent claims of a low closure temperature (c. 600~ for the SmNd isotopic system in garnet (Mezger et al., 1992, Burton et al., 1993). We present evidence for a more robust garnet memory under granulite facies conditions.
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SmNd ages for norwegian garnet peridotite
Lithos, 1986Abstract SmNd results for ga-WR-cpx from garnet Iherzolite in Almklovdalen, western Norway, define an isochron with age of 1703 ± 29 Ma and /get = + 4.7 ± 0.7 (2/gs) which falls on a depleted mantle curve. Garnet websterite from the same peridotite body falls close to the Iherzolite isochron.
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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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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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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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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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