Hydrocarbon Potential Evaluation of Shallow Waters West of Accra Basin

Abstract

Exploration activities have intensified in the Tano basin following the discovery of oil and gas in commercial quantities at the Jubilee fields. The analogue Accra-Keta Basin is still under explored but found to be highly prospective. In this context, this research utilized a twenty (20) two dimensional (2D) seismic line and well data comprising of gamma ray log, density log, sonic log, spontaneous potential and resistivity logs. These data sets were used to evaluate the hydrocarbon potential of shallow waters west of Accra-Keta Basin and the results are in three folds. Firstly, it was clear from the well data that there is a gross reservoir thickness of 744.23m, Net of 531.73m and an average porosity of 15.5%. Secondly, from attribute analysis and geophysical interpretation, it was found that, though the area is structurally controlled leading to the compartmentalization, there exist also channels which serve as a very good source of quality sand. Diapiric structures which could serve as trapping mechanism for hydrocarbon were found in addition to gas chimney which is an indication of a working petroleum system. The final volume was calculated based on monte-carlo simulation approach which resulted in a minimum volume 150 million barrel of oil and 309.3 million cubic feet of gas.