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A rock of both metamorphic and igneous origin that exhibits characteristics of both rock types and probably forms through the heating but not melting of rocks in the presence of abundant fluids.

[Greek migma, migmat-, mixture (from mignunai, to mix; see meik- in Indo-European roots) + -ite.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Geological Science) a composite rock body containing two types of rock (esp igneous and metamorphic rock) that have interacted with each other but are nevertheless still distinguishable
[C20: alteration of Swedish migmatit, from Greek migma mixture + -ite1]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Nironen (1997) presented a regional model of the formation of the Svecofennian juvenile crustal domain through (1) continental break-up of the Late Archaean crust and seafloor spreading during 2.1-1.95 Ga, (2) early crust formation at 2.1-1.9 Ga, (3) initiation, development, and compression of subduction zones, and island arcs and between-arc sedimentary basins at 1.91-1.82 Ga, and (4) anatectic potassium granite and migmatite formation during the 1.84-1.81 Ga extensional stage.
The Greater Himalayan Sequence (GHS) of the Bhutan Himalaya is a complex, highly deformed unit of gneiss and migmatite that has been intruded by leucogranite.
This rock unit contains appreciable amounts of biotite schist, migmatite, aplite, and quartz-orthoclase-muscovite-bearing pegmatite subordinate in volume to the granite gneisses.
In addition, the Laguigangri Group containing schist, gneiss, and migmatite units crops out in the core of the Yelaxiangbo dome (Figure 1(b)), as well as some Quaternary sediments composed of gravel, sand gravel, sandy loam, clay, and ice boulder spread in the central and southern areas of the NH [2].
Closer geological and structural observation (Figures 1 & 2) of this anomaly's axes suggested that its general trend followed an inferred granite intrusion area known as So'o granite The quite different nature of the Bouguer gravity map on the northern side was marked by gravity highs, bounded by relatively steep gradients occurring over or near higher metamorphic formations (granulite, migmatite and micaschist) and other granitic plutons, suggesting the existence of a suture zone between two of the crust's blocks (Kennedy, 1964).
The limits of the LTBT basin, at north and northeast, are coincident with a structural accident that separates the metasediments (mainly quartzites and slates) of the Central Iberian Zone (CIZ) defined by Lotze (1945) from the complex of migmatite, schist and granitoids of the Ossa-Morena Zone (OMZ); the northwest limit, represented by a thurst fault, is the socalled "Macico Calcario Estremenho" (MCE) consisting of Jurassic limestone overlaid by siliciclastic sediments dated from Cretaceous up to Miocene; at south and southeast the Tertiary deposits have discontinued limits with the Ossa-Morena Zone (OMZ).
John Kiely was in reflective mood after Migmatite gained his biggest success over flights in the Listed Fishery Lane Hurdle in the hands of David Casey.
And on a very modest card, the John Kielytrained Migmatite is napped to open his account in the Tote Jackpot Maiden.
The complex is about 15 km thick and includes, in stratigraphic order from the bottom, (1) mafic orthogneiss and anorthosite, (2) migmatite gneiss, (3) paragneiss, (4) metagabbro and syenite, and (5) chamockite.
The basement of the region is composed of Archean Fuping Group amphibolite- to granulite-facies metamorphic rocks consisting of tonalite-trondhjemite-granodiorite (TTG) gneisses, migmatite, amphibolite, and minor amounts of supracrustal rocks, with metamorphic ages at ca.
biotite, sillimanite-biotite, flebite-nebulite migmatite with cordierite behind the line.
Clonmel maiden hurdle winner Migmatite is open to improvement, while Museo is fitted with cheekpieces again after running sixth to Antipode at Naas.