Petrographic Studies of Migmatite-Gneiss, Quartzites and Pegmatites Complex in Crusher Area of Lokoja, Kogi State, Nigeria

Abstract

The studied Area is situated in Lokoja Local Government Area of Kogi state, this forms part of the Lokoja sheet on latitudes 07°49'N to 07°51'N and longitude 006°38E to 006°40'E and covers an area of 200km² on a scale of 1: 50,000. The study area is situated in the southern Bida Basin and the Basement complex of Nigeria. However, the major rocks encountered during the fieldwork was migmatitegneiss, porphyroblastic gneiss and pegmatite which is the parts of the migmatite-gneiss complex of the Nigerian Basement. Laboratory analysis (thin section) was conducted to determine the mineralogical composition of the rocks, the minerals include quartz, feldspars, micas and opaque minerals. The research area is characterized by overflowing groundwater which supplies streams and rivers for agricultural and domestic usage. Economically, the major economic minerals of the rocks include feldspar, quartz and micas. The feldspars if in large quantity will be mined for ceramic factories for the production of ceramics, tiles and fillers and enhancer in paint, plastic and rubber. Large clasts of quartz also occur in the pegmatite and can be mined and used to produce abrasive minerals. Quartz can be used in railway blasts, they serve as decorative stones, and they are also used in covering of walls and roofing. The quartzite and gneissic rocks in the study area can be blasted and cut into various sizes and shapes and thus be used for road construction and building design. A variety of uses for metamorphosed gneiss exist in buildings, such as ornamental stone applications etc.