The Classification and Evaluation of an Interlayer Shale Oil Reservoir Based on the Fractal Characteristics of Pore Systems: A Case Study in the HSN Area, China
Abstract
:1. Introduction
2. Materials and Methods
2.1. Geological Setting
2.2. Methodology
3. Results
3.1. Porosity and Permeability of Shale Samples in Chang 7
3.2. Pore Types of Shale Samples in Chang 7
3.3. Pore Network of Shale Samples in Chang 7
3.4. Overall Pore Size Distribution of Shale Samples in Chang 7
4. Discussion
4.1. Fractal Dimensions Calculated from HMIP
4.2. Classification of Pore Systems Based on Fractal Pore System
4.3. Shale Reservoir Classification Based on Pore System Classification
5. Conclusions
- (1)
- Four main types of pores are identified in shale samples from Chang 7 in the HSN area. These include residual intergranular pores, dissolution pores, intercrystalline pores of clay minerals and microfractures. The overall pore size distribution of shale samples predominantly falls within the range of 3 nm to 50 μm.
- (2)
- In the Chang 7 interlayer shale in the HSN area, the pore system exhibits multiple fractal characteristics. A scatter plot with three inflection points divides the pore system into four regions, each corresponding to specific pore radii. Based on this, a classification of pores is conducted, distinguishing them into macropores, mesopores, micropores and ultramicropores. Using the proportions of these different pores within the samples, the samples are categorized into four classes. Standards for porosity and permeability are established for these four reservoir classes.
- (3)
- Based on the established standards for porosity and permeability in reservoir classification, the planar distribution of different reservoir types becomes clearly defined. There is a notable difference in the daily oil production from wells across different types of reservoirs. Class I reservoirs exhibit higher daily oil production as the reservoir thickness increases.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Pore Systems | Macropore | Mesopore | Micropore | Ultramicropore |
---|---|---|---|---|
Pore radius (μm) | >0.2 | 0.2–0.08 | 0.08–0.03 | <0.03 |
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Lu, C.; Wang, X.; Ma, S.; Li, S.; Xue, T.; Li, Q. The Classification and Evaluation of an Interlayer Shale Oil Reservoir Based on the Fractal Characteristics of Pore Systems: A Case Study in the HSN Area, China. Fractal Fract. 2024, 8, 167. https://doi.org/10.3390/fractalfract8030167
Lu C, Wang X, Ma S, Li S, Xue T, Li Q. The Classification and Evaluation of an Interlayer Shale Oil Reservoir Based on the Fractal Characteristics of Pore Systems: A Case Study in the HSN Area, China. Fractal and Fractional. 2024; 8(3):167. https://doi.org/10.3390/fractalfract8030167
Chicago/Turabian StyleLu, Changsheng, Xixin Wang, Shuwei Ma, Shaohua Li, Ting Xue, and Qiangqiang Li. 2024. "The Classification and Evaluation of an Interlayer Shale Oil Reservoir Based on the Fractal Characteristics of Pore Systems: A Case Study in the HSN Area, China" Fractal and Fractional 8, no. 3: 167. https://doi.org/10.3390/fractalfract8030167