Aim: This study presents the log analysis results of a log suite comprising gamma ray (GR), resistivity (LLD), neutron (PHIN), density (RHOB) logs and a 3D seismic interpretation of Tymot field located in the southwestern offshore of Niger delta. This study focuses essentially on reserves estimation of hydrocarbon bearing sands. Well data were used in the identification of reservoirs and determination of petrophysical parameters and hydrocarbon presence. Three horizons that corresponded to selected well tops were mapped after well-to-seismic tie. Structural depth maps were created from the mapped horizons. The structural style is dominated by widely spaced simple rollover anticline bounded by growth faults, and this includes down-to-basin faults, antithetic faults and synthetic faults. The petrophysical values – the porosity, net-to-gross, water saturation, hydrocarbon saturation that were calculated yielding  an average porosity value  of 0.23, water saturation of 0.32 and an average net-to-gross value of 0.62. Three horizons H1, H2 and H3 were mapped. The three horizons marked the tops of reservoir sands and provide the structures for hydrocarbon accumulation. Hydrocarbon in-place was estimated. The total hydrocarbon proven reserves for the mapped horizons H1, H2, and H3 were estimated to be 39.04MMBO of oil and 166.13BCF for sand E.

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Interference of ground roll energy on true seismic reflection records has continued to pose a serious challenge to exploration geophysicists. In view of this, amplitude and power spectra of the Rayleigh waves which are the precursor of the ground roll energy were derived from over 70 raw monitor records and plotted as a function of frequency. The objective is to determine the locus of ground energy in the seismic records, analyse their dispersion pattern and suggests viable ways of suppressing them. The results of the amplitude spectrum plots revealed that Rayleigh waved exhibit oscillatory behavior with very high-amplitude values, which correspond to the locus of ground roll energy. This energy is confined to very low frequency range of about 4-9Hz. The Power spectrum which was given as the square of the amplitude as a function of frequency showed appreciable lobes of breaths of the ground roll energy of about 0.5-0.7cm and their trend of dispersions. The power spectrum plots revealed several peaks excluding the early peaks that are direct indication of ground roll energy. The plots showed pronounced and constant decline in energy levels with increasing frequency and reaching very low decibel values of -60Db to -80Db at frequency range of 50Hz. This indicates that the environment is dispersive in nature which probably results from velocity layering. This is a precursor to seismic noise which among others can be suppressed in the field by designing filters with sharper cut off characteristics.

Earth's surface configuration is in constant change due to geomorphic processes in operation. These processes are responsible for initiating several features such as channels, drainage basins, incised valleys, and submarine canyons. The understanding of these features is paramount for an accurate assessment of biological, environmental and geologic activities on land and in the sea. This article is a review of submarine canyons with overview of their geomorphic processes which discusses the origin, types and processes within canyons. Working with a compiled highly published materials of the world's most famous submarine canyons, this paper documents the historical evolution of the canyons over time and the different processes acting in the development of these canyons. From this study, the major factor controlling canyon creation is the seal level change. Turbiditic flow, and tectonics (faults and folds) favours canyon development. Canyon geometry can be both U-shaped, V-shaped or both depending on the tectonic or erosional influence. Although several works have been done on submarine canyon, the issue of submarine canyon evolution through time is minimal and accurate fluvial to canyon head connections are still a challenge. More focus on the stratigraphic and source to sink study of canyon systems can help give clue on the ages of canyons and the type of facies contained in it. This could be of benefit to the oil and gas industry in reservoir explorations.

Despite exploration and production success in Niger Delta, several failed wells have been encountered due to overpressures.Hence, it is very essential to understand the spatial distribution of pore pressure and the generating mechanism in order to mitigate the pitfalls that might arise during drilling. This research provides estimates of pore pressure along three offshore wells using the Eaton's transit time method. An accurate normal compaction trend was estimated using the Eaton's exponent (m=3). Our results show that there are three pressure magnitude regimes: normal pressure zone (hydrostatic pressure), Transition pressure zone (slightly above hydrostatic pressure), and over pressured zone (significantly above hydrostatic pressure). The top of the geopressured zone (2873 mbRT or 9425.853 ft) averagely marks the onset of overpressurization with the excess pore pressure ratios above hydrostatic pressure varying averagely along the three wells between P * = 1.06 -24.75 MPa and the lithostatic load range is λ = 0.46 -0.97 and λ * = 0.2 -0.9. The parametric study shows that the value of Eaton's exponent (m = 3-6) need to be applied with caution based on the dominant pore pressure generating mechanism in the Niger Delta. The generating mechanisms responsible for high pore pressure in the Offshore Niger Delta are disequilibrium compaction, unloading (fluid expansion) and shale diagenesis.

There is a growing interest in the Niger Delta hydrocarbon field exploration and exploitation. With growing interest in proven field prospects and confirmed reservoir facies, there is a need for improved basin and field scale reservoir identification, analysis, and assessment. The Agbada Formation of the middle Miocene age across Vim Field, in the western part of the coastal swamp depobelt was studied using wire-line logs, 3D seismic and biostratigraphic data. This contribution evaluated stratigraphic configuration, structural style, facies geometry, hydrocarbon leads, and distribution. The method adopted involves delineating lithologies from the gamma-ray log, identifying reservoirs from the resistivity and gamma ray logs, well top correlation using gamma ray logs, horizon and fault mapping, time to depth conversion of maps using velocity model, attribute analysis, and sequence stratigraphic analysis. Bounding surfaces were mapped on the seismic section, and well correlations were conducted and integrated with a paleobathymetry chart to highlight the depositional environments. Eight major stratigraphic bounding surfaces (four sequence boundaries and four maximum flooding surfaces) were identified. Erosional bounding surfaces were mapped as interest surface horizons. Analysis of the vertical succession of depositional facies revealed five 3rd order depositional sequences of Mid-Miocene age-bound SB and MFS chronologically. Three strata stacking patterns (progradational, retrogradation, and aggradational) were delineated and interpreted as lowstand systems tract (LST), highstand systems tract (HST), and transgressive systems tract (TST). The alternation of the reservoir sands of the HST and TST and the shale units of the TST offers good traps for hydrocarbon. Fault analysis revealed regional growth faults, counter-regional growth faults, synthetic and antithetic faults that show foot walls and hanging walls dominating the mainly extensional zone. These faults play a major role in hydrocarbon trapping within the area. The depositional environment spans from shelf to slope margin, with sediments deposited within the Inner neritic through the middle neritic to the outer neritic settings. Interpretative observation shows that thin-bedded shale facies complexly intercalate the reservoir facies of the TST. Thus careful evaluation of such reservoirs is recommended before making exploitation decisions.