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Sm-Nd Isotopic Data and Earth's Evolution
Science, 1996Samuel A. Bowring and Todd Housh (1) report Sm/Nd isotopic data giving a wide range of initial ENd values, from +3.5 to -4 at 4.0 billion years ago (Ga) and from +4 to -7 at 3.6 Ga. Their samples were from the Acasta gneisses of northern Canada, which represent the oldest known outcrops of continental crust (2).
S, Moorbath, M J, Whitehouse
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Sm-Nd chronology and petrogenesis of mesosiderites
Geochimica et Cosmochimica Acta, 1994We have obtained Sm-Nd data from four mesosiderite silicate clasts, including three clasts with a variety of textures from the Vaca Muerta type 1A mesosiderite and one gabbroic clast from the Mt. Padbury mesosiderite. The gabbroic Vaca Muerta Pebble 12 and basaltic Pebble 16 yield identical ^(147)Sm- ^(143)Nd ages of 4.48 ± 0.19 AE and 4.48 ± 0.09 AE ...
Stewart, Brian W. +2 more
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Sm-Nd isotopic provinces of the Aldan Shield
Doklady Earth Sciences, 2006The formation of the Early Precambrian continental crust is among the most topical problems of modern geology and petrology and has remained a subject of debate for several decades. The Sm‐Nd isotopic mapping, which occupies an important place among modern methods developed for the solution of this issue, makes it possible to estimate the relative ...
A. B. Kotov +6 more
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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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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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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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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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