scholarly journals Lithofacies and Environmental Analysis of Reservoir Sandstones in the “ABOM” Oilfield of Eastern Niger Delta, Nigeria

2020 ◽  
pp. 34-43
Author(s):  
O. Omoboh Jonathan ◽  
Minapuye I. Odigi
Keyword(s):  
Niger Delta ◽  
Well Log ◽  
Facies Association ◽  
Marine Clay ◽  
Depositional Processes ◽  
Reservoir Sandstones ◽  
Mouth Bar ◽  
Depositional Cycles ◽  
Sand Bodies ◽  
Depositional Cycle

Facies of part of the Coastal swamp depobelt was analyzed using well log. Electrofacies was defined based on well log signatures. The defined facies were inter-related to define a facies association. The facies association were related to deltaic depositional cycles. 10 of such facies association or deltaic cycles were seen in the interval studied. The facies association or deltaic cycles have a different composition of facies related to the level of preservation of the components of the association. The component of the facies association seen include marine clay facies, lower shoreface facies, upper shoreface facies, prograding mouth bar facies and fluvial facies. The marine clay facies underlie each facies association and the channel / prograding mouth bar cap the association where it is preserved. The lower shoreface facies, upper shorefacies, prograding mouth bar and fluvial facies form the Reservoir sandstones. The identified facies association was seen to be repeated in the interval studied though with different composition. This reflects different deltaic depositional cycles with different component of facies due to the prevailing depositional processes occurring at the period of deposition and those affecting the deposit of the cycles after deposition. The arrangements of the different components of the facies within the facies association will help in the prediction of reservoir sand bodies in any deltaic depositional cycle.

scholarly journals Petrophysical evaluation of reservoir sand bodies in Kwe Field Onshore Eastern Niger Delta

2016 ◽  
Vol 20 (2) ◽  
pp. 383-393
Author(s):  
T.M. Asubiojo ◽  
S.E. Okunuwadje
Keyword(s):  
Niger Delta ◽  
Depositional Environment ◽  
Gamma Ray ◽  
Petrophysical Properties ◽  
System Quality ◽  
Flow Units ◽  
Wireline Logs ◽  
And Performance ◽  
Niger Delta Basin ◽  
Sand Bodies

Reservoir sand bodies in Kwe Field, coastal swamp depobelt, onshore eastern Niger Delta Basin were evaluated from a composite log suite comprising gamma ray, resistivity, density and neutron logs of five (5) wells with core photographs of one (1) reservoir of one well. The aim of the study was to evaluate the petrophysical properties of the reservoirs while the objectives were to identify the depositional environment and predict the reservoir system quality and performance. The study identified three reservoir sand bodies in the field on the basis of their petrophysical properties and architecture. Reservoir A has an average NTG (61.4 %), Ø (27.50 %), K (203.99 md), Sw (31.9 %) and Sh (68.1 %); Reservoir B has an average NTG (65.6 %), Ø (26.0 %), K (95.90 md), Sw (28.87 %) and Sh (71.13 %) while Reservoir C has an average NTG (70.4 %), Ø (26.1 %), K (91.4 md), Sw (25.0 %) and Sh (75.03 %) and therefore show that the field has good quality sandstone reservoirs saturated in hydrocarbon. However, the presence of marine shales (or mudstones) interbedding with these sandstones may likely form permeability baffles to vertical flow and compartmentalize the reservoirs. These reservoirs may therefore have different flow units. Integrating wireline logs and core data, the reservoir sand bodies were interpreted as deposited in an estuarineshoreface setting thus indicating that the Kwe Field lies within the marginal marine mega depositional environment.Keywords: Estuarine, Shoreface, Reservoir, Sand, Kwe, field

scholarly journals Hydrocarbon reservoir characterization of “Otan-Ile” field, Niger Delta

2021 ◽  
Vol 11 (2) ◽  
pp. 601-615
Author(s):  
Tokunbo Sanmi Fagbemigun ◽  
Michael Ayu Ayuk ◽  
Olufemi Enitan Oyanameh ◽  
Opeyemi Joshua Akinrinade ◽  
Joel Olayide Amosun ◽  
...  
Keyword(s):  
Niger Delta ◽  
Reservoir Characterization ◽  
Water Saturation ◽  
Structural Deformation ◽  
Well Log ◽  
Reservoir Properties ◽  
Good Tool ◽  
Log Data ◽  
Hydrocarbon Reservoir ◽  
Hydrocarbon Saturation

AbstractOtan-Ile field, located in the transition zone Niger Delta, is characterized by complex structural deformation and faulting which lead to high uncertainties of reservoir properties. These high uncertainties greatly affect the exploration and development of the Otan-Ile field, and thus require proper characterization. Reservoir characterization requires integration of different data such as seismic and well log data, which are used to develop proper reservoir model. Therefore, the objective of this study is to characterize the reservoir sand bodies across the Otan-Ile field and to evaluate the petrophysical parameters using 3-dimension seismic and well log data from four wells. Reservoir sands were delineated using combination of resistivity and gamma ray logs. The estimation of reservoir properties, such as gross thickness, net thickness, volume of shale, porosity, water saturation and hydrocarbon saturation, were done using standard equations. Two horizons (T and U) as well as major and minor faults were mapped across the ‘Otan-Ile’ field. The results show that the average net thickness, volume of shale, porosity, hydrocarbon saturation and permeability across the field are 28.19 m, 15%, 37%, 71% and 26,740.24 md respectively. Two major faults (F1 and F5) dipping in northeastern and northwestern direction were identified. The horizons were characterized by structural closures which can accommodate hydrocarbon were identified. Amplitude maps superimposed on depth-structure map also validate the hydrocarbon potential of the closures on it. This study shows that the integration of 3D seismic and well log data with seismic attribute is a good tool for proper hydrocarbon reservoir characterization.

scholarly journals Disequilibrium Compaction, Fluid expansion and unloading effects: Analysis from well log and its pore pressure implication in Jay Field, Niger Delta

2020 ◽  
pp. 389-400 ◽  
Author(s):  
Chukwuemeka Patrick Abbey ◽  
Meludu Chukwudi Osita ◽  
Oniku Adetola Sunday ◽  
Mamman Yusuf Dabari
Keyword(s):  
Acoustic Wave ◽  
Pore Pressure ◽  
Niger Delta ◽  
Sedimentary Basins ◽  
Burial Depth ◽  
Well Log ◽  
Major Mechanism ◽  
Porosity And Permeability ◽  
Well Log Analysis ◽  
Pressure Regime

     Disequilibrium compaction, sometimes referred to as under compaction, has been identified as a major mechanism of abnormal pore pressure buildup in sedimentary basins. This is attributed to the interplay between the rate at which sediments are deposited and the rate at which fluids associated with the sediments are expelled with respect to burial depth. The purpose of this research is to analyze the mechanisms associated with abnormal pore pressure regime in the sedimentary formation. The study area “Jay field” is an offshore Niger Delta susceptible to abnormal pore pressure regime in the Agbada –Akata formations of the basin. Well log analysis and cross plots were applied to determine the under compacted zone in the formation since compaction increases with burial depth. It was observed that porosity and permeability of the deeper depth (3700 m to end of Well) are higher than those of the shallow part (3000 – 3700 m). This is against what is expected from normal compacted sediment, demonstrating disequilibrium compaction in deposition. Furthermore, it reveals that sedimentation rate was high, making it unable for the sediments to expunge its fluid as expected. Density and acoustic wave increase with depth in normal compaction trend. However, the reverse that was identified in the mapped interval is attributed to disequilibrium compaction, unloading, clay diagenesis, and fluid expansion. The cross plot divulges sediments at the deeper depth had lower density and acoustic wave value with increased porosity when compared to those at shallow depth. This forms the basis that the sediments from this mapped interval experienced disequilibrium and unloading traceable to clay diagenesis during and after deposition, respectively.

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