Geology and Occurrences of Limestone and Marble in Nigeria

Abstract

Limestone occurs only in the sedimentary basins in Nigeria. It occurs mainly in the Benue Trough (Lower, Middle and Upper), Sokoto, Dahomey and Borno (Chad) Basins. Limestone-forming environments (shallow coastal marine conditions), appear to have occurred several times in the geological history of the basins. However, the limestone deposits of the Benue Trough (Lower, Middle and Upper), appear to contain the largest and most economically viable limestone resources in the country. Nearly all the limestone deposits in the country are used for the manufacture of cement. Marble, a metamorphosed limestone occurs within the migmatite-gneiss-schist-quartzite complex as relicts of sedimentary carbonate rocks. These are Upper Proterozoic schist belt metasediments which are normally marked by a general absence of carbonates. Such marble deposits appear to be limited to the western portions of the south and central parts of the country. Several of these marble deposits are currently being exploited for cement (Ukpilla and Obajana) and decorative stone (Jakura, Kwakuti and Igbetti) with some production of ground rock for industrial use. Limestone and marble are among the few industrial minerals and rocks that have been utilized to any great extent in the country. This article summarizes the information available on the country’s limestone and marble deposits (the geology, occurrences, characteristics, reserves, production and quality). Recommendations are proposed for developing the limestone and marble industry to make a positive contribution to the national economy.

Keywords: Nigeria, Sedimentary, Precambrian, Calcite, Dolomite, Carbonate Rocks.