Geology, Petrology and Petrographic Analysis of Ruwan Tabo Area, Northwestern Nigeria

Abstract

The study area overlies the Nigerian basement complex that is made up of Liberian to Pan African rock units, falling within latitudes 110 17’ 00” N and 110 21’20.27” N and longitudes 080 18’ 43.33” E and 080 21’ 33.33” E, in the northern part of the
country, covering an area of 40km2, mapped at a scale of 1:25,000. The area was mapped using compass clinometer and GPS,
rock samples were collected using hammer and chisel and then taken to the laboratory for thin sectioning. Structures were
measured and recorded. Petrologically, the rock units mapped in the area are gneiss, covering about 50% of the total area,
coarse-grained granite which covers about 40% of the total area of study, while the remaining 10% constitutes the minor rocks.
Gneisses and granites from the major rock types in the area, while migmatite, pegmatites and laterites form the minor components of the rock units in the area. Pertographically, the gneiss consists of biotite (10%), plagioclase (25%), quartz (20%), orthoclase (7%), microcline (30%) and muscovite (11%), while the coarse-grained granite consists of biotite (10%), plagioclase (15%), quartz (15%), orthoclase (8%) and microcline (45%) as essential minerals. Structurally, faults, foliations, joints, and veins are the main structures observed in the study area and are mostly attributed to the effects of Pan-African Orogeny which resulted in the N-S trending pattern of the structures in the associated lithologies.