Hydrocarbon play assessment of any hydrocarbon reservoir unit depends on the porosity, permeability, hydrocarbon saturation and water saturation of petrophysical model distributions and seismic reflections of reservoir rocks. The objective of the study is to resolve the ambiguities that are associated with hydrocarbon play assessment of an X-field in the Niger Delta basin. This was achieved through the use of pre-conditioned attributes, fault delineating seismic attributes such as coherence, variance and quantitative definition of the reservoir units of petrophysical model distributions, through the adoption of an integrated methodology of 3D seismic and well log data. A quick look examination of the well log signatures revealed numerous reservoir sand units, but only three hydrocarbon-bearing reservoir sands were of interest to us (RS1, RS2 and RS3). From the quantitative interpretation of well logs, the three identified reservoir sands were evaluated in terms of porosity, permeability, hydrocarbon saturation, shale volume, movable hydrocarbon index and water saturation. Effective porosity values of 24.56, 23.01 and 24.00% were obtained for Well 1, Well 2 and Well 4, respectively. This supports the known or already established porosity range of Agbada Formation of Niger Delta with range 28-32%. The hydrocarbon saturation for RS2 is 68.51% for Well 4, for RS3 72.49% for Well 3 and for RS2 74.16% and for RS3 77.34% for Well 2. RS2 of 79.51% and RS3 of 80.99% for Well 1 were obtained. This shows how prolific the reservoir sand units are with hydrocarbon accumulation tendencies. Structural analysis revealed a highly faulted system that depicts a typical tectonic setting of the Niger Delta basin, and the computed attributes like coherence, and variance shows an optimum visualization of the faulting system. This implies that the trapping mechanism of the field is of both anticlinal and fault-assisted closure and also the viability of the reservoir units is high from the computed petrophysical parameters.

This study had been executed employing Seismic Refraction Tomography (SRT) and Multichannel Analysis of Surface Waves (MASW), to integrate elastic and bearing capacity with engineering criteria within delineation for seismic microzonation besides menace assessment. Forty-eight and eight SRT and MASW outline through an aggregate distance of about 484 m breathe constrained toward characterizing topsoil variables conducive to site characterization. 12 kg sledge hammers with 1.0 m diameter aluminum disc, twenty-four channels (ES 30000S) enhancement seismographs were used as seismic sources, detectors, and recorders. P and S wave’s velocities breathe attained as well as delineated employing SRT and MASW techniques via beget 2D/3D velocity-depth model. The elastic, bearing capacity and engineering parameters calculated were: elastic/ rigidity modulus, Poisson ratio, allowable capacity, compactness grade along with strain correlation to evaluate the near-surface substratum through geophysical and engineering potential. These parameters identified three microzones: Higher, midway, and bottom zones. The higher zone is delineated by frail soil quality; the midway one is delineated by light soil quality and the bottom zone is delineated by acceptable soil quality. The frail and light parameters of the higher and midway zones lead to the structural collapse experience in the region. Therefore, the bottom zone of acceptable soil and rock quality is recommended for the construction plan.

Real-time integrated drilling is an important practice for the upstream petroleum industry. Traditional pre-drill models, tend to offset the data gathered from the field since information obtained prior to spudding and drilling of new wells often become obsolete due to the changes in geology and geomechanics of reservoir-rocks or formations. Estimating the complicated non-linear failure-time of a rock formation is a difficult but important task that helps to mitigate the effects of rock failure when drilling and producing wells from the subsurface. In this study, parameters that have the strongest impact on rock failure were used to develop a numerical and computational model for evaluating wellbore instability in terms of collapse, fracture, rock strength and failure-time. This approach presents drilling and well engineers with a better understanding of the fracture mechanics and rock strength failureprediction procedure required to reduce stability problems by forecasting the rock/formation failuretime. The computational technique built into the software, uses the stress distribution around a rock formation as well as the rock's responses to induced stress as a means of analyzing the failure time of the rock. The results from simulation show that the applied stress has the most significant influence on the failure-time of the rock. The software also shows that the failure-time varied over several orders of magnitude for varying stress-loads. Thus, this will help drilling engineers avoid wellbore failure by adjusting the stress concentration properly through altering the mud pressure and well orientation with respect to in-situ stresses. As observed from the simulation results for the failure time analysis, the trend shows that the time dependent strength failure is not just a function of the applied stress. Because, at applied stress of 6000-6050 psi there was time dependent failure whereas, at higher applied stress of 6350-6400 psi there was no time dependent strength failure.

This study was carried out using five digitized aerogravity data to delineate near-surface structural faults, cavities, low-density zones and estimate the mass balance unit in foundations. Qualitative and quantitative analysis were performed in order to examines the depths to anomalous bodies, density/mass and stratigraphic features such as faults and cavities. The techniques employed were: Source parameter imaging (SPI), 3D Euler deconvolution, forward and inverse modeling. The results of the SPI shallow values range from -5.62 to -53.74 m and deep values range from 3.33 to 120 m. The 3D Euler deconvolution results range from -1892.2 to -1278.3 m for obscure and -12264 to 644.6 m for superficial formations. The forward and inverse modeling result shows the values of depth ranging from 2.5 to 4.8 km, density/mass range from (0.7 to 2.4) x 10-3 kg/m3 and (27 to 133) x 1010 kg of three profiles which is the parameter contrast of the gravity surveys. This shows sequential depths and density/mass contrast between the body of interest and the surrounding material which depicts the presents of faults, sedimentary basins and rock bearing minerals of shale/marble which comprises of air, water and sediment-filled formations. The information from this study has revealed the true nature of the subsurface and this will serve as a guide during road construction.