Lithofacies, Depofacies and Reservoir Characteristics of Well TMG-08, Opolo Field, Niger Delta

Abstract

Sediments within the depth intervals of 2834-6620.9 ft in Well TMG-08 of Opolo Field, Niger Delta, were investigated with the aim of establishing its lithofacies, depositional environments and petrophysical characteristics using a suite of Well-Logs. The Shale lithology is more dominant and of thicker units than the sand at the upper section of the log which could be interpreted as sediments of the Akata Formation. Five sand bodies were identified within the study interval. The shapes of the gamma ray signatures were funnel, cylindrical and symmetrical. Prograding, aggradational and combined prograding and retrograding parasequences were identified from the stacking patterns of the gamma ray curves. The environments of deposition delineated were Transgressive shelf sands and mixed Tidal flat environment, Crevasse splay, River mouth bar, Delta front shoreface, and Fluvial channels, Tidal sands, Prograding delta distributaries. The predicted porosity and permeability show moderate to good quality reservoirs. The average porosity value (0.13 *100= 13% Ranging from Poor to moderate), with a moderate permeability Value (16.87mD) due to the presence of high volume of shale in the reservoirs. The thicknesses of the reservoir are small averaging 5.5ft (16.92m). The depositional environment shows that sand B and C are continuous within the reservoir. The environment of deposition of the study area lies within the marginal marine