Field mapping and petrographic analyses were conducted on the migmatites in the Buzaye area part of sheet 149 Bauchi NE to evaluate their morphological units and petrographic characteristics. Field mapping revealed migmatite with stromatic structures represented the metatexite while parts of the migmatite with schollen and schlieren structures with granitic component represented the diatexite. Fourteen rock samples from different outcrops were cut and examined for mineralogical compositions under petrographic investigations. Thin section analysis revealed occurrence of quartz, plagioclase, orthopyroxene, microcline, biotite, garnet and shows metamorphic imprints in microscopic such as undulous extinction in quartz, elongation of biotite, and obliteration in albite twinning, implying greenschist to amphibolite facies for the migmatites. The morphological continuity observed in the field across the paleosome – stromatic metatexite- schlieren diatexite transition is mirrored by progressive changes in texture and mineralogy which suggests that anatexis and crustal reworking in the study area occurred as an essentially closed system process.
Key words: Migmatite,Metatexite,Diatexite,Stromatic,Schieren,Petrography
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