Geology and petrography of Sabon Garin Kara and environs part of Malumfashi sheet 79 NE Nigeria

Abstract

The study area is about 40 km2 that is (8 km × 5 km) which is located in Gwarzo Local Government area of Kano State part of  Malumfashi sheet 79NE which lies within Longitude E07°57’19.5” and E08°00’00” and Latitude N11° 51’30”andN11°47‘00. Major rock types identified include medium grained biotite-muscovite granite, coarse grained muscovite-biotite granites, quartz-syenite, and quartz-monzonites. Most of the crystals show subhedral to anhedral form and a perfect cleavage is somehow visible. The interference colours observed under cross-polarized light include blue, dark grey, light grey, some pinkish colour and brown colour which disappear upon the stage rotation. Albite and Carlsbad twinning are seen and used to identify the feldspars. Various structural features were observed with NE- SW trend which represents the final imprint of the Pan-African orogeny. Key words: Biotite, granite, cross-polarized, twinning.