Scholarly works
Permanent URI for this collectionhttps://repository.ui.edu.ng/handle/123456789/411
Browse
2 results
Search Results
Item Pore pressure detection and risk assessment of OBL oil field, offshore Niger delta, Nigeria(2014) Nton, M. E.; Ayeni, M. D.The Niger Delta is a prolific petroleum sedimentary basin in the Gulf of Guinea and is posed with a major challenge of overpressure development in many of its fields. Integrated study, utilizing 3D seismic data and well logs from four wells, namely; OBL_1, OBL_2, OBL_4 and OBL_5 was carried out in the offshore Niger Delta. The study aims at evaluation of structural influences on pressure development, detection of overpressure zones and consequently examining the risk involved in drilling. Log signatures show decrease in density log values and corresponding increase in sonic log readings in wells OBL_1, OBL_2 and OBL_4. Well OBL_5, reveals increase density log values but decrease sonic log readings. Two regional and few minor faults observed to penetrate the overpressure zones were mapped out and integrated with the surfaces of the tops of the over pressured zones to generate three stratigraphic zones. Aside from under compaction mechanism, the regional faults penetrating the surfaces generated across the overpressure intervals could have influenced pressure development in the wells.Item Sequence stratigraphic framework of K-field in part of Western Niger delta, Nigeria(2011) Nton, M. E.; Ogungbemi, T. S."A sequence stratigraphic approach was applied to K-Field, within the western Niger Delta by integrating wireline logs of four wells; 001,003, 004 and 005; and high resolution biostratigraphic data of wells 001, 004 and well 005. The study is aimed at deducing key bounding surfaces, depositional sequences and their corresponding systems tracts as well as the palaeodepositional environment of the hydrocarbon bearing Agbada Formation in the study area. Two sequence boundaries at 8900 ft (2697 m) and 9050 ft (2742 m), and one maximum flooding surface at a depth of 7650 ft (2318 m) were recognized in well 5 and used to subdivide the stratigraphic succession into depositional sequences and their corresponding systems tracts. Highstand and Transgressive systems tracts were recognized in each of the three depositional sequences. Marker shale, characterized by Chloguebelina 3 (16.0 Ma) was used to date the key bounding surfaces with the aid of the Niger Delta chronostratigraphic chart as Early to Late Miocene. The Highstand systems tracts are characterized by shale-rich upward coarsening sands, having poor reservoir quality while the lowstand systems tracts are characterized by thick sandstone units, indicating good quality seals to reservoirs. From the SP logs motifs, the depositional environments inferred include tidal channel, shoreface and shelf environments which typify a marine depositional setting. "