Reservoir evaluation of “T-X” field (Onshore, Niger delta) from well log petrophysical analysis

Abstract

Three wells A1, A2 and A3 were identified on the 'T-X' field in onshore Niger Delta. A comprehensive petrophysical analysis on one of the wells (well A1) was carried out in order to come up with physical properties such as shale volume, porosity (Φ), permeability (K), fluid saturation, and net pay thickness, among others for future development planned of the oil field. A well log data from this field have been examined and analyzed. The logs include gamma ray (used for the identification of lithology), resistivity and porosity logs (used for delineating hydrocarbon bearing reservoirs). Wireline log analysis was employed in the characterization of the reservoirs in the well studied; the hydrocarbon sands were delineated by the use of gamma ray, resistivity and density/neutron from which the reservoir quality were determined. Fluid types defined in the reservoirs on the basis of neutron/density log signatures were basically water, oil and gas.Eighteen (18) reservoirs (AR1 to AR18) were identified, among which twelve (12) are hydrocarbon-bearing reservoirs. Permeability and porosity values range between 1-6206md and 6-28% respectively. Water saturation recorded between 15-100% in the identified reservoirs which indicated that the proportion of void spaces occupied by water varied from low to high values, thus, indicating both low and high hydrocarbon saturation. Plot of hydrocarbon saturation and porosity showed a linear trend and strong linear relationships between permeability and porosity was also observed in all the reservoirs identified indicating that they are permeable and have pores that are strongly interconnected. This study has really demonstrated that petrophysics has a vital role to play in reservoirs characterization.

Spatial Variation of Reservoir Properties in Onshore Dove Field of the Niger Delta Region, Nigeria

“…Permeability ModelExamination of the permeability model ranged from 600mD to 1600mD, with high permeability ranges of 800mD to 1200mD at the north-east section of the wells. This result agrees with the findings of other authors in the Niger Delta such asOluwatoyin 2016, Saadu and Nwankwo 2018, and Orji et al 2019 …”

Paleokinematic reconstruction and wellbore breakout analysis of in situ stress orientation in a Niger Delta Oilfield: Implications for tectonic reactivation in Nigeria

“…Shale diapirism due to loading of poorly compacted, over-pressured, prodeltaic and delta-slope clays resulted in the deposition of the Akata Formation, the continental intercalaire (Abija, 2019; Tse and Ogunyemi, 2016) by the higher density delta-front sands of the Agbada Formation (Bakare, 2006). This was followed by slope instability caused by lack of lateral basinward support for the under-compacted delta slope clays of the Akata Formation (Oluwatoyin, 2016 (Doust and Omatsola, 1990). Subsidence and supply rates interplay resulted in deposition of discrete depobelts.…”

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

“…Depositional environment may consist of one or few lithofacies spread through its body). A reservoir is a subsurface rock that has effective porosity and permeability which contains commercially exploitable quantity of hydrocarbon (Ologe, 2016). Reservoir characteristics involves the determination of the physical properties of reservoir (ability to store and transmit fluid) units and change in their distribution throughout the reservoir.…”