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AMCG complexes

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Journal Article
Journal: GSA Bulletin
Published: 01 November 2004
GSA Bulletin (2004) 116 (11-12): 1299–1317.
..., however, are more difficult to apply when there exists a high-grade metamorphic overprint, as in the Adirondacks. The origin of AMCG complexes has remained controversial for decades, and three competing models have emerged. The first of these proposes that most, if not all, members of the suite...
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Journal Article
Published: 01 August 2010
The Canadian Mineralogist (2010) 48 (4): 969–990.
...Aku P. Heinonen; O. Tapani Rämö; Irmeli Mänttäri; Bo Johanson; Reijo Alviola Abstract The ~1640 Ma Ahvenisto AMCG complex in southeastern Finland is the most prominent occurrence of massif-type anorthosite and associated monzodioritic rocks in the Fennoscandian rapakivi suite. The petrology...
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Journal Article
Published: 17 November 2014
Journal of the Geological Society (2015) 172 (1): 103–112.
...Aku Heinonen; Tom Andersen; O. Tapani Rämö; Martin Whitehouse Abstract The isotope compositions of massif-type anorthosites in Proterozoic anorthosite–mangerite–charnockite–granite (AMCG) complexes are commonly dominated by crustal values. Olivine-bearing anorthositic rocks in several AMCG suites...
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Series: GSA Special Papers
Published: 01 January 1990
DOI: 10.1130/SPE246-p301
... Field evidence, as well as binary and ternary variation diagrams, provide evidence that the anorthosite-mangerite-charnockite-granite gneiss (AMCG) suite of the Adirondacks evolved in bimodal magmatic complexes without a continuous line of liquid descent from mafic through acidic igneous...
Journal Article
Published: 01 August 2010
The Canadian Mineralogist (2010) 48 (4): 729–750.
...–1140 Ma) of the ca. 1200–1140 Ma Shawinigan orogeny. Emplacement of many other anorthosite – mangerite – charnockite – granite (AMCG) suites also correlates with the waning stage of orogeny and includes the ca. 1155 Ma Morin and Lac-Saint-Jean complexes, the ca. 1650 Ma Mealy Mountain complex...
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Journal Article
Published: 01 August 2010
The Canadian Mineralogist (2010) 48 (4): 947–968.
... conditions. This is another line of evidence that, in anorthosite – mangerite – charnockite – granite (AMCG) complexes, two different crustal source-rocks can produce two different suites of rocks during the same melting episode. Abstract Les mécanismes de différenciation et les roches sources des...
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Journal Article
Published: 28 November 2005
Canadian Journal of Earth Sciences (2005) 42 (10): 1865–1880.
...Claude Hébert; Anne-Marie Cadieux; Otto van Breemen Abstract In the south-central Grenville Province, Quebec, Canada, anorthosite-mangerite-charnockite-granite (AMCG) magmatism took place during four distinct episodes between 1327 and 1008 Ma. AMCG rocks crosscut several gneiss complexes composed...
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Journal Article
Published: 01 August 2010
The Canadian Mineralogist (2010) 48 (4): 751–761.
... represented in high-grade terranes worldwide ( e.g., Ashwal 1993 , and references therein). The origin of AMCG complexes has remained controversial for decades, and three competing models have emerged. Model 1 proposes that most, if not all, members of the suite are comagmatic and related by fractional...
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Journal Article
Published: 01 August 2010
The Canadian Mineralogist (2010) 48 (4): 763–786.
... (AMCG) suite, and whether or not all compositions are comagmatic. Oxygen isotope ratios in igneous rocks are a sensitive tracer of source and contaminant materials that had a low-temperature aqueous origin, and thus are a good probe for sediments and other supracrustal materials in magmas ( e.g...
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Journal Article
Published: 02 April 2000
Canadian Journal of Earth Sciences (2000) 37 (2-3): 359–383.
... magmatic arc on southeastern Laurentia during the Mesoproterozoic implies that other coeval magmatism inboard from the arc took place in a back-arc setting. Such magmatism was widespread and chemically diverse and included large volume “anorogenic” anorthosite–mangerite–charnockite–granite (AMCG) complexes...
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Journal Article
Published: 01 March 1997
Canadian Journal of Earth Sciences (1997) 34 (3): 299–316.
... arc plutons (La Bostonnais complex). A tonalitic orthogneiss yielding a zircon age suggests that most of the structurally underlying Mékinac and Shawinigan domains consist of orthogneisses that may be high-grade equivalents of the La Bostonnais complex. A voluminous metasedimentary unit occurring...
Image
Distribution of <b>AMCG</b> suites and ferroan-potassic (A-type and rapakivi) gran...
Published: 01 August 2010
F ig . 1. Distribution of AMCG suites and ferroan-potassic (A-type and rapakivi) granites across North America and western Europe. Symbols: AD: Adirondack Mountains, G: Granite–Rhyolite province, HC–L: Horse Creek and Laramie AMCG complexes, M: Mazatzal orogen, N: Nain AMCG complex, R: Rogaland
Image
Oxygen isotope transect of the Frontenac suite and other <b>AMCG</b> (anorthosite-...
in > Geosphere
Published: 01 December 2013
Figure 6. Oxygen isotope transect of the Frontenac suite and other AMCG (anorthosite-mangerite-charnockite-granite) related granitoids across the Adirondack Highlands, Frontenac terrane, and Sharbot Lake domain of the Elzevir terrane, showing δ 18 O zircon values as a function of distance
Journal Article
Journal: Geosphere
Published: 01 April 2011
Geosphere (2011) 7 (2): 333–356.
...-granite (AMCG) plutonism. Neodymium T DM ages from the Pyrites Complex range from 1440 to 2650 Ma, are not compatible with derivation from a typical depleted mantle reservoir, and suggest, along with incompatible element concentrations, that these rocks record mantle enrichment, presumably during...
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Published: 06 October 2006
DOI: 10.1130/2006.fld008(06)
EISBN: 9780813756080
...-mangerite-charnockite-granite (AMCG) association, and also include amphibolite-facies gneisses of felsic to mafic bulk composition. The overlying Paleozoic quartzite and carbonate ± semipelite succession records only greenschist-facies metamorphism, with on-going debate as to the extent of Taconian, Acadian...
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Journal Article
Journal: GSA Bulletin
Published: 01 November 2006
GSA Bulletin (2006) 118 (11-12): 1283–1298.
..., electron microprobe analyses of monazites from the southern highlands reveal multiple age zones, including cores with ages of ca. 1170–1180 Ma, consistent with primary growth during Shawinigan orogenesis, complex zones formed ca. 1140–1155 Ma during AMCG magmatism, and ca. 1050–1020 Ma formed during...
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Journal Article
Journal: GSA Bulletin
Published: 01 July 2008
GSA Bulletin (2008) 120 (7-8): 950–961.
... access through its conduit system. The results of this study, as well as data previously obtained from east-central Adirondack samples ( Heumann et al., 2006 ), reveal a complex history of melt formation, reflecting Shawinigan (1210–1160 Ma), AMCG (ca. 1155 Ma), Hawkeye (ca. 1103–1095 Ma...
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Series: GSA Memoirs
Published: 01 January 2004
DOI: 10.1130/0-8137-1197-5.337
... Sensitive high-resolution ion microprobe (SHRIMP) analyses of zircons from four charnockitic gneisses and a ferrodiorite dike belonging to the anorthosite-mangerite-charnockite-granite (AMCG) suite of the Adirondack Mountains are consistent with prior multigrain U-Pb zircon determinations...
Journal Article
Journal: GSA Bulletin
Published: 06 July 2017