Formation Evaluation and Reservoir Quality Assessment of the AN-field Offshore Douala/Kribi Campo Basin, Cameroon

Document Type : Research Paper

Authors

1 Department of Geology, University of Buea, Cameroon

2 Department of Petroleum and Geological Engineering, University of Guyana, Turkeyen Campus, Georgetown, Guyana

10.22078/jpst.2025.5506.1944

Abstract

The AN field, located offshore in the Douala Sub-Basin within the Douala/Kribi-Campo Basin, is part of the larger Aptian Salt Basin in Equatorial West Africa. This study focuses on evaluating the petrophysical properties and determining the reservoir quality of the sandstones in the AN Field to enhance production efficiency. Furthermore, well log data, including caliper, gamma-ray, density, neutron, sonic, and resistivity logs, were collected from Well 1 and Well 2 (pseudonym) in the AN field Douala Basin and analyzed using Techlog version 2015.1 software for petrophysical analysis and reservoir quality assessment. Moreover, the lithologic sequence consists of sandstone beds alternating with shale. In addition, three sandy reservoir units were identified (R1, R2, and R3), with thicknesses ranging from 16.6 to 53.8 m, identified in Wells 1 and 2. In addition, the reservoirs exhibited poor average formation porosity (1.54 - 16.53%), low average permeability (0.02 - 5.93 mD), and significantly high average water saturation (64.81-99.1%). In addition, analysis of true formation resistivity values versus water saturation indicated that all reservoir units in both wells were water saturated and unable to yield a commercial quantity of hydrocarbons. Furthermore, the gamma-ray log patterns indicate the depositional environment to be a deep marine setting, specifically fan valley sediments, encompassing braided river floodplains, deep tidal channel fills, and submarine fan lobes. In addition, the identified depositional environment aligns with a deep marine setting, which emphasizes the need for further exploration and assessment to optimize production efficiency in this area. Moreover, the results from this study will guide wellsite decisions, reservoir development, and production planning, and impact critical financial decisions at every stage of the Exploration and Production lifecycle in the Douala Sub-Basin, Cameroon.

Keywords

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