Screening and Ranking of Chad Basin for co 2 Sequestration Potential in Nigeria

Abstract

ABSTRACT Sedimentary basins are suitable to different degrees for CO 2 geological sequestration as a result of various intrinsic and extrinsic characteristics. This paper preliminarily screened and ranked the Chad Basin of Nigeria sector based on Bachu (2003) ranking and screening criteria adapted which includes factors such as tectonic setting, basin size and depth, geology, hydrogeology, hydrocarbon potentials, climate, geothermal, existing resources and industry maturity. For each criterion i (i = 1…5) used for the evaluation of basin suitability, monotonically -increasing numerical function f i is assigned, which are continuous or discrete, to describe a value placed on a specific class j for that criterion. The lowest and the highest functions of this functions characterize the worst and best class in terms of suitability for that criterion, i.e. f i,1 = min (f i ), where and f i,n = max (f i ); where ( n = 3, 4 or 5).The criteria relate to either the containment security, the volume of storage capacity achievable, or considering the economic or technological feasibility. The results shows that Chad basin has R k score value of 0.53 against the f i, n = max (f i ) value equal to 1 as highest value of the function characterize the best in terms of suitability for the criterion in which this ranking are based on. Regional screening and ranking of the entire basins are recommended while detailed local site characterisation of the basin is needed to assess its overall suitability for CO 2 sequestration potentials, since countries like Cameroon, Central African Republic, Niger, Chad, and Nigeria shares the basin on regional leve