Determination of Reservoir Sand Body Using Well-C in Niger Delta

Abstract

There are several techniques which can be used to determine the depositional environment of a sedimentary rock. the technique include the determination of sedimentary structures, fossil records, logging etc. This work was carried out on Well-C located in the Niger Delta region of Nigeria. The Niger Delta basin is the most prolific and economic sedimentary basin in Nigeria. The depositional environment has been described by many workers which lay emphasis on sedimentary environment as having certain processes operating within discernible spatial framework. The Niger Delta basin, also referred to as the Niger Delta Province, is an external rift basin located in the Niger Delta and Gulf of Guinea on the passive continental margin near the western coast of Nigeria with suspected or proven access to Cameroon, Equatorial Guinea and Sao Tome and Principe. The Niger Delta has been pro-grading since the Eocene with truncation at intervals by marine transgressions on either local or regional scales. The three major sedimentary environments are the continental, transitional and the marine environments which are represented by Benin, Agbada and Akata formations respectively. Petroleum in the Niger Delta is produced from the sandstone and unconsolidated sands predominantly in the Agbada formation. in order of standard of the standard of geological approach required for the interpretation of portable depositional environments and research qualities of the C-Well reservoir sand bodies, analysis and interpretation (Gamma Ray Logs) gotten from the Well-C was done. the gamma ray is used to measure the radioactivity of the formation. In sedimentary formations, the log normally reflects the shale content of the formation. The results of the well log readings in the figures provided. A total of nine sand bodies were recognized and their thickness and log shapes delineated. The C-Well reservoir is interpreted as deposits associated with a coastal barrier island system formed in a progradational wave dominated coastline environment with tidal current influence. The sand occurs with laminated silts and clay towards the base and become clay/silt free sand upwards. They show funnel shaped log signatures that are serrated at the bottom, which could be attributed to sedimentation rate exceeding the rate subsidence. It is recommended that further work should be done in the study area using different dada such as seismic data, core log to further prove adequate properties of the well.