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1.
《International Geology Review》2012,54(6)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
2.
《International Geology Review》2012,54(1)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
3.
《International Geology Review》2012,54(8)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
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《International Geology Review》2012,54(4)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
5.
《International Geology Review》2012,54(4)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
6.
《International Geology Review》2012,54(6)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
7.
《International Geology Review》2012,54(1)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
8.
《International Geology Review》2012,54(8)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
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《International Geology Review》2012,54(10)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
10.
《International Geology Review》2012,54(7)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
11.
《Australian Journal of Earth Sciences》2013,60(3)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
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《Australian Journal of Earth Sciences》2013,60(2)
Abstract This is a scanned image of the original Editorial Board page(s) for this issue 相似文献
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Jonas Mota e Silva Cesar Fonseca Ferreira Filho Bernhard Bühn Elton Luiz Dantas 《Mineralium Deposita》2011,46(1):57-90
The “Americano do Brasil” Complex (ABC) is part of a cluster of coeval synorogenic mafic–ultramafic intrusions emplaced during
the Brasiliano/Pan-African Orogenic Cycle in Brazil. The medium-sized ABC consists of interlayered dunite, peridotite, websterite,
and gabbronorite. High Fo values of olivine (up to Fo88) and the crystallization sequence of the ABC (Ol + Chr ≥ Ol + Opx + Chr ≥ Cpx + Opx ≥ Opx + Pl + Cpx ≥ Opx + Pl + Cpx + Ilm + Mag)
suggest crystallization from tholeiitic high-MgO parental magmas. Light rare earth element (REE)-enriched mantle-normalized
REE profiles and εNd(T) values of +2.4 for cumulate rocks from the ABC suggest a depleted mantle source for the parental magma.
The ABC Ni–Cu sulfide deposit (3.1 Mt at 1.12 wt.% Ni and 1.02 wt.% Cu) consists of three distinctively different orebodies
(S1, S2, and G2). The S2 orebody, an unusual occurrence of stratiform massive sulfide hosted by dunite and peridotite in the
interior of a layered intrusion, results from sulfides accumulated at the transient base of the magma chamber following a
new influx of parental magma. The G2 orebody has an irregular and roughly cylindrical shape, consisting mainly of net-textured
sulfides. The G2 orebody is hosted by peridotite and pyroxenite and located stratigraphically below the S1 orebody. S2 and
G2 orebodies are characterized by low Cu/Cu + Ni ratios (mainly below 0.4). The S1 orebody, hosted by websterite and gabbronorite
in the more fractionated sequence of the ABC, is a cluster of several irregular discontinuous orebodies of Ni–Cu disseminated
sulfides. The sulfides of the S1 orebody have high Cu/Cu + Ni ratios (mainly between 0.5 and 0.8) and are highly depleted
in PGE. The S1 orebody is interpreted to result from a later event of sulfide segregation in the magma chamber, possibly following
the event that originated the G2 orebody. The bulk of δ34S values for sulfides of the ABC orebodies and their host rocks fall in the range of 0 ± 2‰. Higher δ34S values (between 3‰ and 5‰) are restricted to pyrite from xenoliths of gneiss located close to the S1 orebody and sulfides
from the S1 orebody. Crustal xenoliths and chemical data (lithogeochemistry and sulfur isotope composition) provide evidence
of crustal contamination of the igneous rocks hosting the S1 orebody, suggesting that sulfur saturation was induced by contamination
with sulfide-bearing crustal rocks. The ABC deposit is an example of Ni–Cu sulfide mineralization hosted by synorogenic mafic–ultramafic
intrusions. The S2 orebody is the first documented example of an economic stratiform massive sulfide orebody located within
layered intrusions, expanding the opportunities for exploration of Ni–Cu sulfides in orogenic regions worldwide. 相似文献
19.
《International Geology Review》2012,54(1)