A New Fracture Characterization Method Using Petrophysical Model With Inherent Anisotropy and Borehole Data
Yongping Wang
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorCorresponding Author
Jingye Li
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Correspondence: Jingye Li ([email protected])
Search for more papers by this authorWeiheng Geng
Department of Automation, Beijing National Research Center for Information Science and Technology (BNRist), Tsinghua University, Beijing, China
Search for more papers by this authorQiyu Yang
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorLei Han
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorYuning Zhang
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorYongping Wang
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorCorresponding Author
Jingye Li
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Correspondence: Jingye Li ([email protected])
Search for more papers by this authorWeiheng Geng
Department of Automation, Beijing National Research Center for Information Science and Technology (BNRist), Tsinghua University, Beijing, China
Search for more papers by this authorQiyu Yang
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorLei Han
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorYuning Zhang
College of Geophysics, China University of Petroleum (Beijing), Beijing, China
State Key Laboratory of Petroleum Resources and Engineering, China University of Petroleum (Beijing), Beijing, China
Search for more papers by this authorFunding: Financial support was provided by the R&D Department of China National Petroleum Corporation (Investigations on fundamental experiments and advanced theoretical methods in geophysical prospecting applications, 2022DQ0604-04).
ABSTRACT
Fractures represent a critical structural feature in unconventional reservoirs, as they create essential pathways for the migration and accumulation of oil and gas. Therefore, fracture characterization is a fundamental task in the exploration of unconventional hydrocarbon resources. Conventional fracture characterization methods typically do not account for the inherent anisotropy of the formation, which arises from the sedimentary environment and fluid distribution, often leading to inaccurate fracture predictions. To address this challenge, we propose a petrophysical model that incorporates inherent anisotropy, employing rock physics modelling to accurately characterize fracture distribution. Furthermore, to reduce the substantial workload involved in manually calibrating the petrophysical model, we introduce a one-dimensional convolutional neural network combined with an attention mechanism. By leveraging the advanced nonlinear learning capabilities of the convolutional neural network, we aim to fit the petrophysical model and extend its application across all exploration wells and the entire field. The effectiveness and feasibility of the proposed method are demonstrated through experiments using actual borehole data from a fracture-dominated reservoir.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
References
- Aghli, G., R. Moussavi-Harami, and B. Tokhmechi. 2020. “Integration of Sonic and Resistivity Conventional Logs for Identification of Fracture Parameters in the Carbonate Reservoirs (A Case Study, Carbonate Asmari Formation, Zagros Basin, SW Iran).” Journal of Petroleum Science and Engineering 186: 106728.
- Aguilera, R. 1998. “Geologic Aspects of Naturally Fractured Reservoirs.” Leading Edge 17, no. 12: 1667–1670.
10.1190/1.1437912 Google Scholar
- Bakulin, A., V. Grechka, and I. Tsvankin. 2000. “Estimation of Fracture Parameters From Reflection Seismic Data—Part II: Fractured Models With Orthorhombic Symmetry.” Geophysics 65, no. 6: 1803–1817.
- Bouchaala, F., A. A. Mohamed, M. S. Jouini, Y. Bouzidi, and M. Y. Ali. 2023. “Azimuthal Investigation of a Fractured Carbonate Reservoir.” SPE Reservoir Evaluation & Engineering 26, no. 03: 813–826.
10.2118/212873-PA Google Scholar
- Brajanovski, M., B. Gurevich, and M. Schoenberg. 2005. “A Model for P-Wave Attenuation and Dispersion in a Porous Medium Permeated by Aligned Fractures.” Geophysical Journal International 163, no. 1: 372–384.
- Casini, G., D. W. Hunt, E. Monsen, and A. Bounaim. 2016. “Fracture Characterization and Modeling From Virtual Outcrops.” AAPG Bulletin 100, no. 1: 41–61.
- Chen, C., X. Yin, Z. Chen, X. Liu, and J. Wang. 2023. “An Approximate Method for Calculating Anisotropy Parameters and Reflectivity of Shales With Horizontal Fractures.” Journal of Geophysics and Engineering 20, no. 5: 993–1005.
- Chen, H., X. Yin, S. Qu, and G. Zhang. 2014. “AVAZ Inversion for Fracture Weakness Parameters Based on the Rock Physics Model.” Journal of Geophysics and Engineering 11, no. 6: 065007.
- Cleary, M. P., S. M. Lee, and I. W. Chen. 1980. “Self-Consistent Techniques for Heterogeneous Media.” Journal of the Engineering Mechanics Division 106, no. 5: 861–887.
- Crampin, S. 1981. “A Review of Wave Motion in Anisotropic and Cracked Elastic-Media.” Wave Motion 3, no. 4: 343–391.
- Crampin, S. 1984. “Effective Anisotropic Elastic Constants for Wave Propagation Through Cracked Solids.” Geophysical Journal International 76, no. 1: 135–145.
- Dong, S., L. Wang, L. Zeng, et al. 2023. “Fracture Identification in Reservoirs Using Well Log Data by Window Sliding Recurrent Neural Network.” Geoenergy Science and Engineering 230: 212165.
- Dong, S., L. Zeng, J. Liu, et al. 2020. “Fracture Identification in Tight Reservoirs by Multiple Kernel Fisher Discriminant Analysis Using Conventional Logs.” Interpretation 8, no. 4: SP215–SP225.
- Gao, S., L. Gong, X. B. Liu, et al. 2020. “Distribution and Controlling Factors of Natural Fractures in Deep Tight Volcanic Gas Reservoirs in Xujiaweizi Area, Northern Songliao Basin.” Oil & Gas Geology 41, no. 3: 503–512.
- Guo, J., T. Han, L. Y. Fu, D. Xu, and X. Fang. 2019. “Effective Elastic Properties of Rocks With Transversely Isotropic Background Permeated by Aligned Penny-Shaped Cracks.” Journal of Geophysical Research: Solid Earth 124, no. 1: 400–424.
- Gurevich, B. 2003. “Elastic Properties of Saturated Porous Rocks With Aligned Fractures.” Journal of Applied Geophysics 54, no. 3–4: 203–218.
- He, S., K. Meng, C. Wang, et al. 2023. “Fracture Identification Using Conventional Logs in Ultra-Low Permeability Sandstone Reservoirs: A Case Study of the Chang 6 Member of the Ordos Basin, China.” Minerals 13, no. 2: 297.
- Hill, R. 1952. “The Elastic Behaviour of a Crystalline Aggregate.” Proceedings of the Physical Society. Section A 65, no. 5: 349.
- Hudson, J. A. 1980. “Overall Properties of a Cracked Solid.” In Mathematical Proceedings of the Cambridge Philosophical Society. Cambridge University Press.
- Hudson, J. A. 1981. “Wave Speeds and Attenuation of Elastic Waves in Material Containing Cracks.” Geophysical Journal International 64, no. 1: 133–150.
- Kelishami, S. B. A., R. Mohebian, and O. Salmian. 2022. “A Comprehensive Perspective on Pore Connectivity and Natural Fracture Analysis in Oligo-Miocene Heterogeneous Carbonates, Southern Iran.” Journal of Petroleum Science and Engineering 208: 109199.
- Kiranyaz, S., T. Ince, O. Abdeljaber, O. Avci, and M. Gabbouj. 2019. “1-D Convolutional Neural Networks for Signal Processing Applications.” In ICASSP 2019—2019 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE.
- Koren, Z., I. Ravve, and R. Levy. 2010. “Moveout Approximation for Horizontal Transversely Isotropic and Vertical Transversely Isotropic Layered Medium. Part II: Effective Model.” Geophysical Prospecting 58, no. 4: 599–617.
- Liu, E., and A. Martinez. 2012. Seismic Fracture Characterization: Concepts and Practical Applications. EAGE.
- Liu, J., Z. Gui, G. Gao, Y. Li, Q. Wei, and Y. Liu. 2023. “Predicting Shear Wave Velocity Using a Convolutional Neural Network and Dual-Constraint Calculation for Anisotropic Parameters Incorporating Compressional and Shear Wave Velocities.” Processes 11, no. 8: 2356.
- Mavko, G., T. Mukerji, and J. Dvorkin. 2009. The Petrophysical Handbook. 2nd ed. Cambridge University Press.
- Mazhari, S. M., H. Memarian, and B. Tokhmechi. 2018. “A Hybrid Learning Automata and Case-Based Reasoning for Fractured Zone Detection Using Petrophysical Logs.” Arabian Journal of Geosciences 11, no. 19: 577.
- Narr, W., D. S. Schechter, and L. B. Thompson. 2006. Naturally Fractured Reservoir Characterization. Society of Petroleum Engineers.
10.2118/9781613999615 Google Scholar
- Norris, A. N., P. Sheng, and A. J. Callegari. 1985. “Effective-Medium Theories for Two-Phase Dielectric Media.” Journal of Applied Physics 57, no. 6: 1990–1996.
- Nouri-Taleghani, M., M. Mahmoudifar, A. Shokrollahi, A. Tatar, and M. Karimi-Khaledi. 2015. “Fracture Density Determination Using a Novel Hybrid Computational Scheme: A Case Study on an Iranian Marun Oil Field Reservoir.” Journal of Geophysics and Engineering 12, no. 2: 188–198.
- Nur, A. 1971. “Effects of Stress on Velocity Anisotropy in Rocks With Cracks.” Journal of Geophysical Research 76, no. 8: 2022–2034.
- Ortega, O. J., R. A. Marrett, and S. E. Laubach. 2006. “A Scale-Independent Approach to Fracture Intensity and Average Spacing Measurement.” AAPG Bulletin 90, no. 2: 193–208.
- Pan, S., B. Yang, S. Wang, et al. 2023. “Oil Well Production Prediction Based on CNN-LSTM Model With Self-Attention Mechanism.” Energy 284: 128701.
- Sayers, C. M. 2010. Geophysics Under Stress: Geomechanical Applications of Seismic and Borehole Acoustic Waves. Society of Exploration Geophysicists and European Association of Geoscientists and Engineers.
10.1190/1.9781560802129 Google Scholar
- Schoenberg, M., and J. Douma. 1988. “Elastic Wave Propagation in Media With Parallel Fractures and Aligned Cracks.” Geophysical Prospecting 36, no. 6: 571–590.
- Schoenberg, M., and K. Helbig. 1997. “Orthorhombic Media: Modeling Elastic Wave Behavior in a Vertically Fractured Earth.” Geophysics 62, no. 6: 1954–1974.
- Schoenberg, M., and C. M. Sayers. 1995. “Seismic Anisotropy of Fractured Rock.” Geophysics 60, no. 1: 204–211.
- Shalaby, M. R., and M. A. Islam. 2017. “Fracture Detection Using Conventional Well Logging in Carbonate Matulla Formation, Geisum Oil Field, Southern Gulf of Suez, Egypt.” Journal of Petroleum Exploration and Production Technology 7: 977–989.
- Sublette, V., C. Sicking, and G. Treadgold. 2008. “Estimating HTI in the Presence of Strong VTI.” In SEG International Exposition and Annual Meeting. SEG.
- Sun, W., Y. F. Li, J. W. Fu, and T. Y. Li. 2014. “Review of Fracture Identification With Well Logs and Seismic Data.” Progress in Geophysics 29, no. 3: 1231–1242.
- Tariq, Z., M. Murtaza, M. Mahmoud, M. S. Aljawad, and M. S. Kamal. 2022. “Machine Learning Approach to Predict the Dynamic Linear Swelling of Shales Treated With Different Waterbased Drilling Fluids.” Fuel 315: 123282.
- Thomsen, L. 1986. “Weak Elastic Anisotropy.” Geophysics 51, no. 10: 1954–1966.
- Tokhmchi, B., H. Memarian, and M. R. Rezaee. 2010. “Estimation of the Fracture Density in Fractured Zones Using Petrophysical Logs.” Journal of Petroleum Science and Engineering 72, no. 1–2: 206–213.
- Tsuneyama, F., and G. Mavko. 2005. “Velocity Anisotropy Estimation for Brine-Saturated Sandstone and Shale.” Leading Edge 24, no. 9: 882–888.
10.1190/1.2056371 Google Scholar
- Tsvankin, I. 1996. “P-Wave Signatures and Notation for Transversely Isotropic Media: An Overview.” Geophysics 61, no. 2: 467–483.
- Wang, J., J. Cao, J. Fu, and H. Xu. 2022. “Missing Well Logs Prediction Using Deep Learning Integrated Neural Network With the Self-Attention Mechanism.” Energy 261: 125270.
- Wang, Z. 2002. “Seismic Anisotropy in Sedimentary Rocks, Part 2: Laboratory Data.” Geophysics 67, no. 5: 1423–1440.
- Wilson, T. H., V. Smith, and A. Brown. 2013. “Developing a Strategy for CO2 EOR in an Unconventional Reservoir Using 3D Seismic Attribute Workflows and Fracture Image Logs.” In SEG International Exposition and Annual Meeting. SEG.
- Wilson, T. H., V. Smith, and A. Brown. 2015. “Developing a Model Discrete Fracture Network, Drilling, and Enhanced Oil Recovery Strategy in an Unconventional Naturally Fractured Reservoir Using Integrated Field, Image Log, and Three-Dimensional Seismic Data.” AAPG Bulletin 99, no. 4: 735–762.
- Xie, W., G. He, L. Li, et al. 2020. “Azimuthal Anisotropy Analysis of Wide-Azimuth P-Wave Seismic Data for Fracture Orientation and Density Characterization in a Tight Gas Reservoir.” Interpretation 8, no. 1: SA73–SA83.
- Xu, J., B. Zhang, Y. Qin, G. Cao, and H. Zhang. 2016. “Method for Calculating the Fracture Porosity of Tight-Fracture Reservoirs.” Geophysics 81, no. 4: IM57–IM70.
- Yin, X., M. A. Zhengqian, W. Xiang, and Z. Zong. 2022. “Review of Fracture Prediction Driven by the Seismic Rock Physics Theory (I): Effective Anisotropic Seismic Rock Physics Theory.” Geophysical Prospecting for Petroleum 61, no. 2: 183–204.
- Zazoun, R. S. 2013. “Fracture Density Estimation From Core and Conventional Well Logs Data Using Artificial Neural Networks: The Cambro-Ordovician Reservoir of Mesdar Oil Field, Algeria.” Journal of African Earth Sciences 83: 55–73.
- Zhou, X., R. Wang, D. Xia, et al. 2023. “Fracture Prediction of Tight Sandstone Reservoirs Using Outcrops and Log Curve-Based Extremum Method: A Case Study of the Chang 7 Member of the Yanchang Formation in Block X, Ordos Basin.” Unconventional Resources 3: 164–175.
- Zhu, J., H. Chen, and W. Ye. 2020. “Classification of Human Activities Based on Radar Signals Using 1D-CNN and LSTM.” In 2020 IEEE International Symposium on Circuits and Systems (ISCAS). IEEE.