This study examines the different morphologies of migmatites in the Zongor area, north eastern Nigeria, based on field and petrological evidences. Field relationship exposes rocks around the Zongor area as dominated by a complex suite of migmatites that have undergone different stages of metamorphism. In some parts of the area, structures such as layering and foliation are seen to have been preserved during partial melting, whereas in other parts, these structures appear to have been completely consumed during anatexis to form new structures. This discrepancy in the field occurrence of migmatites in the area, in line with recent development in studies on migmatites has shed more insight into the classification of the migmatites in the study area. Rock samples from the field are sorted into groups. Representative rock samples from these groups are studied under thin section. The occurrence of high temperature minerals like garnet, orthopyroxene, plagioclases, olivine and hornblende are indicative of high-grade metamorphism. Results from field and petrographic studies are compared with results from the works of Sawyer, 2009. Using his first and second order classification scheme as a guide for the morphological classification of the migmatites in the area, the migmatites are grouped into metatexite and diatexites. The geologic conditions and mode of occurrence of the migmatites in the Zongor area are studied in order to understand the tectonic history of the area and its implication for mineral occurrence
Key words: Migmatites, metamorphism, partial melting, anatexis, metatexites and diatexites
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