Comparative study of Petrophysical Properties in Bentiu & Aradeiba Formations & Their implication to Reservoir Quality

Abstract

In this study wire line logging data of exploration well Laloba AG-1 in Muglad basin were analyzed in order to discriminates between the petro-physical properties in Aradeiba & Bentiu formations and accordingly to identify the formation of better reservoir quality. The petro-physical properties used were: shale volume (Vsh), total & effective porosities (PhiT & PhiE) as well as water saturation (Sw). Aradeiba formation was found to be more enriched in shale as compared to Bentiu which is cleaner. The Vsh in Aradeiba range between (0.17) to (0.9) with average value of (0.65), while Bentiu has Vsh range between (0) to (1) with average value of (0.44). The net to gross ratio was found to be (0.63) to (0.74) in Aradeiba, while in Bentiu (0.67) to (0.46) net to gross range was observed. The average effective porosity in Aradeiba formation was (0.23), while in Bentiu it was found to be (0. 22). The average water saturation in Aradeiba was found to be (0.8), while for Bentiu it averages about (0.89). The pay reservoir thickness in Aradeiba at zone one (1.83) and zone two (4.42) and in Bentiu at zone three (13.11), zone four (5.05) and zone five (4.42). Accordingly, Bentiu formation was found to be of better reservoir quality and more prolific compared to Aradeiba.