scholarly journals Reservoir Characterization of Buma Field Reservoirs, Niger Delta using Seismic and Well Log Data

2019 ◽  
Vol 2 (4) ◽  

The reservoir characterization of Buma Field, Niger Delta using seismic and well log data is the focus of this research. Seismic data in SEG-Y format and suites of well logs have been used to achieve the aim and objectives of the research. Methodologies used in this work are standard methods used in this kind of research. Results of the analysis seismic data shows fifteen faults have been identified, nine trend NW-SE and are antithetic faults whereas the six trend NESW and are synthetic faults. These faults formed closures and could act as trapping mechanisms for hydrocarbon in the identified horizons/reservoirs. Two hydrocarbon bearing horizons D and F have been mapped on the seismic and analysis of the well logs showed that sand and shale are major lithologies in the studied wells. Well correlation showed similarities in geological properties such as lithology, reservoir tops and petrophysical properties. Volumetric estimation carried out on the two reservoirs showed Reservoir D having average thickness of 26.73 ft., area of 3784.89 acres, bulk volume of 4407x106 ft3 , net volume of 4226x106 ft3 , pore volume of 216 x106 RB, hydrocarbon pore volume (oil) of 143x106 RB and STOIIP of 77 MMSTB. Reservoir F has an average thickness of 41.55 ft., area of 2790.63 acres, bulk volume of 5051x106 ft3, net volume of 4769x10106 ft3 , pore volume of 248x10106 RB, hydrocarbon pore volume (oil) of 167x10106 RB and STOIIP of 88 MMSTB. Integrating results of structural interpretation, well log analysis, petrophysical properties and volumetric estimation it is evident that both reservoirs have very good porosities and excellent permeability, good thicknesses of productive sand and reduced water saturation as to aid storage and easy flow of hydrocarbon pore fluids. Therefore, the two Buma Field Reservoirs D and F are prolific with hydrocarbon pore fluids (oil) which can be exploited economically

2020 ◽  
Vol 8 (4) ◽  
pp. T1057-T1069
Author(s):  
Ritesh Kumar Sharma ◽  
Satinder Chopra ◽  
Larry Lines

The discrimination of fluid content and lithology in a reservoir is important because it has a bearing on reservoir development and its management. Among other things, rock-physics analysis is usually carried out to distinguish between the lithology and fluid components of a reservoir by way of estimating the volume of clay, water saturation, and porosity using seismic data. Although these rock-physics parameters are easy to compute for conventional plays, there are many uncertainties in their estimation for unconventional plays, especially where multiple zones need to be characterized simultaneously. We have evaluated such uncertainties with reference to a data set from the Delaware Basin where the Bone Spring, Wolfcamp, Barnett, and Mississippian Formations are the prospective zones. Attempts at seismic reservoir characterization of these formations have been developed in Part 1 of this paper, where the geologic background of the area of study, the preconditioning of prestack seismic data, well-log correlation, accounting for the temporal and lateral variation in the seismic wavelets, and building of robust low-frequency model for prestack simultaneous impedance inversion were determined. We determine the challenges and the uncertainty in the characterization of the Bone Spring, Wolfcamp, Barnett, and Mississippian sections and explain how we overcame those. In the light of these uncertainties, we decide that any deterministic approach for characterization of the target formations of interest may not be appropriate and we build a case for adopting a robust statistical approach. Making use of neutron porosity and density porosity well-log data in the formations of interest, we determine how the type of shale, volume of shale, effective porosity, and lithoclassification can be carried out. Using the available log data, multimineral analysis was also carried out using a nonlinear optimization approach, which lent support to our facies classification. We then extend this exercise to derived seismic attributes for determination of the lithofacies volumes and their probabilities, together with their correlations with the facies information derived from mud log data.


2020 ◽  
Vol 12 (1) ◽  
pp. 256-274
Author(s):  
Wasif Saeed ◽  
Hongbing Zhang ◽  
Qiang Guo ◽  
Aamir Ali ◽  
Tahir Azeem ◽  
...  

AbstractThe main reservoir in Huizhou sub-basin is Zhujiang Formation of early Miocene age. The petrophysical analysis shows that the Zhujiang Formation contains thin carbonate intervals, which have good hydrocarbon potential. However, the accurate interpretation of thin carbonate intervals is always challenging as conventional seismic interpretation techniques do not provide much success in such cases. In this study, well logs, three-layer forward amplitude versus offset (AVO) model and the wedge model are integrated to analyze the effect of tuning thickness on AVO responses. It is observed that zones having a thickness greater than or equal to 15 m can be delineated with seismic data having a dominant frequency of more than 45 Hz. The results are also successfully verified by analyzing AVO attributes, i.e., intercept and gradient. The study will be helpful to enhance the characterization of thin reservoir intervals and minimize the risk of exploration in the Huizhou sub-basin, China.


2018 ◽  
Vol 6 (2) ◽  
pp. T325-T336 ◽  
Author(s):  
Ritesh Kumar Sharma ◽  
Satinder Chopra ◽  
James Keay ◽  
Hossein Nemati ◽  
Larry Lines

The Utica Formation in eastern Ohio possesses all the prerequisites for being a successful unconventional play. Attempts at seismic reservoir characterization of the Utica Formation have been discussed in part 1, in which, after providing the geologic background of the area of study, the preconditioning of prestack seismic data, well-log correlation, and building of robust low-frequency models for prestack simultaneous impedance inversion were explained. All these efforts were aimed at identification of sweet spots in the Utica Formation in terms of organic richness as well as brittleness. We elaborate on some aspects of that exercise, such as the challenges we faced in the determination of the total organic carbon (TOC) volume and computation of brittleness indices based on mineralogical and geomechanical considerations. The prediction of TOC in the Utica play using a methodology, in which limited seismic as well as well-log data are available, is demonstrated first. Thereafter, knowing the nonexistence of the universally accepted indicator of brittleness, mechanical along with mineralogical attempts to extract the brittleness information for the Utica play are discussed. Although an attempt is made to determine brittleness from mechanical rock-physics parameters (Young’s modulus and Poisson’s ratio) derived from seismic data, the available X-ray diffraction data and regional petrophysical modeling make it possible to determine the brittleness index based on mineralogical data and thereafter be derived from seismic data.


2017 ◽  
Vol 10 (6) ◽  
Author(s):  
Oluseun Adetola Sanuade ◽  
Adesoji Olumayowa Akanji ◽  
Michael Adeyinka Oladunjoye ◽  
Abayomi Adesola Olaojo ◽  
Julius O. Fatoba

2021 ◽  
pp. 1-50
Author(s):  
Yongchae Cho

The prediction of natural fracture networks and their geomechanical properties remains a challenge for unconventional reservoir characterization. Since natural fractures are highly heterogeneous and sub-seismic scale, integrating petrophysical data (i.e., cores, well logs) with seismic data is important for building a reliable natural fracture model. Therefore, I introduce an integrated and stochastic approach for discrete fracture network modeling with field data demonstration. In the proposed method, I first perform a seismic attribute analysis to highlight the discontinuity in the seismic data. Then, I extrapolate the well log data which includes localized but high-confidence information. By using the fracture intensity model including both seismic and well logs, I build the final natural fracture model which can be used as a background model for the subsequent geomechanical analysis such as simulation of hydraulic fractures propagation. As a result, the proposed workflow combining multiscale data in a stochastic approach constructs a reliable natural fracture model. I validate the constructed fracture distribution by its good agreement with the well log data.


2018 ◽  
Author(s):  
Gulnaz Minigalieva ◽  
Albina Nigmatzyanova ◽  
Tatyana Burikova ◽  
Olga Privalova ◽  
Ruslan Akhmetzyanov ◽  
...  

2018 ◽  
Author(s):  
Gulnaz Minigalieva ◽  
Albina Nigmatzyanova ◽  
Tatyana Burikova ◽  
Olga Privalova ◽  
Ruslan Akhmetzyanov ◽  
...  

Author(s):  
Oluwatoyin Khadijat Olaleye ◽  
Pius Adekunle Enikanselu ◽  
Michael Ayuk Ayuk

AbstractHydrocarbon accumulation and production within the Niger Delta Basin are controlled by varieties of geologic features guided by the depositional environment and tectonic history across the basin. In this study, multiple seismic attribute transforms were applied to three-dimensional (3D) seismic data obtained from “Reigh” Field, Onshore Niger Delta to delineate and characterize geologic features capable of harboring hydrocarbon and identifying hydrocarbon productivity areas within the field. Two (2) sand units were delineated from borehole log data and their corresponding horizons were mapped on seismic data, using appropriate check-shot data of the boreholes. Petrophysical summary of the sand units revealed that the area is characterized by high sand/shale ratio, effective porosity ranged from 16 to 36% and hydrocarbon saturation between 72 and 92%. By extracting attribute maps of coherence, instantaneous frequency, instantaneous amplitude and RMS amplitude, characterization of the sand units in terms of reservoir geomorphological features, facies distribution and hydrocarbon potential was achieved. Seismic attribute results revealed (1) characteristic patterns of varying frequency and amplitude areas, (2) major control of hydrocarbon accumulation being structural, in terms of fault, (3) prospective stratigraphic pinch-out, lenticular thick hydrocarbon sand, mounded sand deposit and barrier bar deposit. Seismic Attributes analysis together with seismic structural interpretation revealed prospective structurally high zones with high sand percentage, moderate thickness and high porosity anomaly at the center of the field. The integration of different seismic attribute transforms and results from the study has improved our understanding of mapped sand units and enhanced the delineation of drillable locations which are not recognized on conventional seismic interpretations.


Sign in / Sign up

Export Citation Format

Share Document