Impact of Stress-Dependent Matrix and Fracture Properties on Shale Gas Production
Abstract
:1. Introduction
2. Model Description
2.1. Stress-Dependent Matrix Permeability
2.2. Stress-Dependent Fracture Permeability and Contact Surface Area
3. Results and Discussions
3.1. The Coupled Effect of Poro-Elastic Compaction and Slip Flow
3.2. The Combined Effect of Stress-Dependent Matrix and Fracture Property on Shale Gas Production
4. Conclusions
- The coupled poro-elastic and slippage model predicts only slightly higher gas production than the model with only the poro-elastic effect or the model with decoupled poro-elastic and gas slippage-effect. The dominant factor that controls the gas production is still the poro-elastic effect (pore volume compaction).
- Fracture surface area loss was found to affect shale gas production, but the impact is not significant compared with the fracture permeability loss.
- The impact of stress-dependent fracture property happens at the very early time during the production, while the impact of stress-dependent matrix property is mainly dominated for the longer-term gas production. The matrix permeability evolution can have a significant impact on shale gas production, especially for cases with highly conductive fractures.
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Parameter | Description | Unit | Value |
---|---|---|---|
pinit | initial pressure | MPa | 26.9 |
pw | well pressure | MPa | 3.4 |
hf | fracture height | m | 50 |
μg | gas viscosity | cp | 0.02 |
initial matrix permeability | nD | 500 | |
φm | matrix porosity | - | 0.06 |
v | Poisson’s ratio | - | 0.2 |
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Tang, H.; Di, Y.; Zhang, Y.; Li, H. Impact of Stress-Dependent Matrix and Fracture Properties on Shale Gas Production. Energies 2017, 10, 996. https://doi.org/10.3390/en10070996
Tang H, Di Y, Zhang Y, Li H. Impact of Stress-Dependent Matrix and Fracture Properties on Shale Gas Production. Energies. 2017; 10(7):996. https://doi.org/10.3390/en10070996
Chicago/Turabian StyleTang, Huiying, Yuan Di, Yongbin Zhang, and Hangyu Li. 2017. "Impact of Stress-Dependent Matrix and Fracture Properties on Shale Gas Production" Energies 10, no. 7: 996. https://doi.org/10.3390/en10070996