Abstract
Textures are important as indicators of processes of migmatization, though they may be profoundly modified by post-migmatization events. Migmatization processes considered in this chapter are anatexis, metamorphic differentiation and segregation of aqueous fluid. The latter fluid is unlikely to segregate as large bodies, but leucosomes may grow gradually from aqueous fluids in fractures (Yardley, 1978). Anatexites usually segregate under the influence of stress (see section 5.6.2), leading to complex leucosome shapes. Segregation of melt may be incomplete or even non-existent: some rocks without discrete leucosomes are treated here, namely the ophthalmites (rocks with porphyroblastic ‘eyes’ of feldspar) of the anatexite suite of McLellan (1983a). Various textural properties will be treated in turn, with discussion of their bearing on the origin and subsequent evolution of leucosomes.
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Ashworth, J.R., McLellan, E.L. (1985). Textures. In: Ashworth, J.R. (eds) Migmatites. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-2347-1_5
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DOI: https://doi.org/10.1007/978-1-4613-2347-1_5
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