Integrated Geochemical and Multivariate Statistical Examination of Source Rocks in the Sokoto and Anambra Basins, Nigeria: Implications for Hydrocarbon Prospectivity
Lukman Musa Adamu,
Nuhu George Obaje,
Okafor Pudentiana Ngozi,
Umar Mohammed Umar
Issue:
Volume 4, Issue 2, December 2020
Pages:
39-50
Received:
21 May 2020
Accepted:
4 June 2020
Published:
15 June 2020
Abstract: The LECO and Rock–Eval pyrolysis for 7 shale and 3 coal samples, as well as, multivariate statistical analysis have been used to probe source rock characteristics, correlation between the assessed parameters (S1, S2, S3, HI, S1 + S2, OI, PI, TOC) and the impact of changes in the Tmax on the assessed parameters in the Sokoto Basin and Anambra Basin of northwestern and southeastern Nigeria respectively. The geochemical results show that 93% of the samples have TOC values greater than the minimum limit value (0.5 wt %) required to induce hydrocarbon generation from source rocks. Meanwhile, the Dukamaje and Taloka shales are found to be fair to good source rock for oil generation with slightly higher thermal maturation. The source rocks are generally immature through sub-mature to marginal mature with respect to the oil and gas window, while the potential source rocks from the Anambra Basin are generally sub-mature grading to mature within the oil window. The analyzed data were approached statistically to find some relations such as factors, and clusters concerning the examination of the source rocks. These factors were categorized into type of organic matter and organic richness, thermal maturity and hydrocarbon potency. In addendum, cluster analysis separated the source rocks in the study area into two groups. The source rocks characterized by HI >240 (mg/g), TOC from 58.89 to 66.43 wt%, S1 from 2.01 to 2.54 (mg/g) and S2 from 148.94 to 162.52 (mg/g) indicating good to excellent source rocks with kerogen of type II and type III and are capable of generating oil and gas. Followed by the Source rocks characterized by HI <240 (mg/g), TOC from 0.94 to 6.68 wt%, S1 from 0.14 to 0.72 (mg/g) and S2 from 0.14 to 3.36 (mg/g) indicating poor to good source rocks with kerogen of type III and are capable of generating gas. Howeverr, Pearson’s correlation coefficient and linear regression analysis shows a significant positive correlation between TOC and S1, S2 and HI and no correlation between TOC and Tmax, highly negative correlation between TOC and OI and no correlation between Tmax and HI.
Abstract: The LECO and Rock–Eval pyrolysis for 7 shale and 3 coal samples, as well as, multivariate statistical analysis have been used to probe source rock characteristics, correlation between the assessed parameters (S1, S2, S3, HI, S1 + S2, OI, PI, TOC) and the impact of changes in the Tmax on the assessed parameters in the Sokoto Basin and Anambra Basin ...
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Potentials of Enzyme Enhanced Oil Recovery: A Review
Tinuola Hannah Udoh,
Lucas Evangelista
Issue:
Volume 4, Issue 2, December 2020
Pages:
51-63
Received:
29 August 2020
Accepted:
14 September 2020
Published:
19 September 2020
Abstract: In this paper, the progresses of understanding of the enzymes application in hydrocarbon production from extensive experimental and field studies are reviewed. Enzyme enhanced oil recovery is an emerging method of improving oil production in an environmentally friendly way, but the mechanisms underlying this process are not clearly understood. Also, detailed studies on enzyme enhanced oil recovery applications are not readily available. From the comprehensive review carried out in this study, we observed that most of the works done on enzyme enhanced oil recovery processes were not properly detailed and the different experimental procedures adopted makes coherent understanding of the process difficult. Evident however in all the studies from the laboratory experiments and field applications, is the capacity of enzyme to improve oil production from both sandstone and carbonate rocks. Also, we have identified and highlighted the physicochemical properties of the enzymes commonly used for enhanced oil recovery and their effects on oil recovery process in order to improve the understanding of their applicability in relevant hydrocarbon reservoir. Furthermore, the challenges and future research directions for enzyme enhanced oil recovery applications have been pinpointed in this study. Having unfold the enhanced oil recovery potential of enzyme, a clarion call is thereby made for deeper studies on this emerging method of improving oil production. This study is relevant to the design and application of enzyme enhanced oil recovery process in both carbonate and sandstone reservoirs.
Abstract: In this paper, the progresses of understanding of the enzymes application in hydrocarbon production from extensive experimental and field studies are reviewed. Enzyme enhanced oil recovery is an emerging method of improving oil production in an environmentally friendly way, but the mechanisms underlying this process are not clearly understood. Also...
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Performance Evaluation of Waterflood Reservoirs in High Water Cut Period Based on New Relative Permeability Model
Issue:
Volume 4, Issue 2, December 2020
Pages:
64-69
Received:
18 September 2020
Accepted:
5 October 2020
Published:
13 October 2020
Abstract: Water flooding performance evaluation and recovery prediction with relatively easy tools has always been among the top aims of reservoir engineering studies, especially for mature reservoirs in high water-cut period. Relative permeability curves are basic required properties reflecting multi-phase flow characteristic and used together with production history to evaluate reservoir performance. In high water-cut period the relative permeability ratio deviate from the empirical straight-line form, which makes traditional models less effective or erroneous in performance prediction. This paper presents a new relative permeability ratio model which can convert the non-linear characteristic of this problem into linear expression. And a new simple water flooding performance analysis technique is developed based on the new model, which can be used to forecast ultimate recovery factor and the corresponding sweep efficiency. The main advantage of this work is taking into account of high water-cut characteristic with less model parameters compared with other improved models. Synthetic case and field examples demonstrated the advantages of this method in parameter solving and consistency in history matching. The proposed technique in this work can be used as predictive analysis tool in forecasting ultimate recovery and performance evaluation for mature water flooding reservoirs.
Abstract: Water flooding performance evaluation and recovery prediction with relatively easy tools has always been among the top aims of reservoir engineering studies, especially for mature reservoirs in high water-cut period. Relative permeability curves are basic required properties reflecting multi-phase flow characteristic and used together with producti...
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