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General Characteristics of Migmatites and Migmatite Terranes
1999Structures and structural relationships resulting from superimposed deformation have long been recognized by geologists, and references to this perception can be found in the literature at least as far back as the late nineteenth century (Clough, The Geology of Cowal (Gunn et al, 1897, pp. 23, 24), and here, under ‘Fold (Structure) sets’, section 5.3),
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Origin and evolution of a migmatite
Contributions to Mineralogy and Petrology, 1982The development of a stromatic migmatite exposed east and southeast of Arvika (Western Sweden) is described in four stages beginning with the country rock and following evolution through three areas characterized by low, medium and high amounts of leucosomes (areas L, M, and H, respectively).
Johannes, W., Gupta, L. N.
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Igneous microstructures in migmatites
Geology, 1988Clear differences between the microstructures of leucosomes and mesosomes occur in some nebulitic migmatites in the Proterozoic Arunta block, central Australia. The leucosomes show crystal faces of K-feldspar (microcline-microperthite), cordierite, andalusite, and plagio clase against quartz, indicating crystallization of a melt.
R. H. Vernon, W. J. Collins
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Melt segregation in migmatites
Journal of Geophysical Research: Solid Earth, 1995Anatectic stromatic migmatites have a symmetrical layered structure with a low ratio of thickness to length and a periodicity, features that have not been explained satisfactorily but which are related to physical processes of melt segregation. We evaluate the compaction model for segregation as it applies to migmatites and develop models for melt ...
Michael Brown +3 more
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Schlieren formation in diatexite migmatite: examples from the St Malo migmatite terrane, France
Journal of Metamorphic Geology, 2003AbstractSchlieren are trains of platy or blocky minerals, typically the ferromagnesian minerals and accessory phases, that occur in granites and melt‐rich migmatites, such as diatexites. They have been considered as: (1) unmelted residue from xenoliths or the source region; (2) mineral accumulations formed during magma flow; (3) compositional layering;
I. Milord, E. W. Sawyer
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1985
The Moines (summaries in Johnstone, 1975; Johnson et al., 1979; Johnson, 1983) are a series of late Precambrian metasediments which have undergone both ‘Grenvillian’ (c. 1000 Ma—Brook et al., 1976) and Caledonian (490–440 Ma—Fettes, 1979) amphibolite facies metamorphism. The effects of tectonic reworking and renewed migmatization on rocks of an earlier
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The Moines (summaries in Johnstone, 1975; Johnson et al., 1979; Johnson, 1983) are a series of late Precambrian metasediments which have undergone both ‘Grenvillian’ (c. 1000 Ma—Brook et al., 1976) and Caledonian (490–440 Ma—Fettes, 1979) amphibolite facies metamorphism. The effects of tectonic reworking and renewed migmatization on rocks of an earlier
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Fluid inclusions in migmatites
1985The fluid inclusions provide petrologists with the only direct method for studying a possible metamorphic fluid from a high P-T environment. Basic principles of a fluid inclusion study are as old as modern petrography (Sorby, 1858), but only in recent years have advances in the technology (heating-freezing stages), and in the understanding of fluid ...
J. Touret, Sakiko N. Olsen
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Killarney Gneisses and Migmatites
Geological Society of America Bulletin, 1927Introduction The Huronian sediments, which stretch almost unbroken from the western end of Lake Superior to a line between Killarney and Lake Temiskaming, end abruptly against an area of gneisses. This area of gneisses, previously thought to be of pre-Huronian age, is now known to be composed in part of rocks younger than the Huronian sediments and ...
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Localised non-migmatitic UHT domains within thermally buffered migmatites
Goldschmidt2023 abstracts, 2023Samantha March +3 more
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1985
The migmatite problem has always been interrelated with the granite problem. The long and sometimes heated debates of the granite controversy between ‘magmatists’ and ‘transformationists’ were ended, for the time being, by Tuttle and Bowen (1958). Their study also convinced many geologists that migmatites were the product of simple partial melting and ...
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The migmatite problem has always been interrelated with the granite problem. The long and sometimes heated debates of the granite controversy between ‘magmatists’ and ‘transformationists’ were ended, for the time being, by Tuttle and Bowen (1958). Their study also convinced many geologists that migmatites were the product of simple partial melting and ...
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