Permeability Estimation of Shale Oil Reservoir with Laboratory-derived Data: A Case Study of the Chang 7 Member in Ordos Basin
Zhang Lin, Gao Li, Ba Jing*, Zhang Meng-Bo, José M. Carcione, and Liu Wei-Hua
1. School of Earth Sciences and Engineering, Hohai University, Nanjing, Jiangsu, 211000.
2. Exploration and Development Research Institute of PetroChina, Changqing Oilfi eld Company, Xi'an Shanxi, 710018.
3. National Institute of Oceanography and Applied Geophysics (OGS), Sgonico, Trieste 34010.
4. Sinopec Geophysical Research Institute, Nanjing, Jiangsu, 211103.
Abstract The shale oil reservoir within the Yanchang Formations of Ordos Basin harbors substantial oil and gas resources and has recently emerged as the primary focus of unconventional oil and gas exploration and development. Due to its complex pore and throat structure, pronounced heterogeneity, and tight reservoir characteristics, the techniques for conventional oil and gas exploration and production face challenges in comprehensive implementation, also indicating that as a vital parameter for evaluating the physical properties of a reservoir, permeability cannot be effectively estimated. This study selects 21 tight sandstone samples from the Q area within the shale oil formations of Ordos Basin. We systematically conduct the experiments to measure porosity, permeability, ultrasonic wave velocities, and resistivity at varying confi ning pressures. Results reveal that these measurements exhibit nonlinear changes in response to eff ective pressure. By using these experimental data and eff ective medium model, empirical relationships between Pand S-wave velocities, permeability and resistivity and eff ective pressure are established at logging and seismic scales. Furthermore, relationships between P-wave impedance and permeability, and resistivity and permeability are determined. A comparison between the predicted permeability and logging data demonstrates that the impedance–permeability relationship yields better results in contrast to those of resistivity–permeability relationship. These relationships are further applied to the seismic interpretation of shale oil reservoir in the target layer, enabling the permeability profi le predictions based on inverse P-wave impedance. The predicted results are evaluated with actual production data, revealing a better agreement between predicted results and logging data and productivity.
Fund: The authors acknowledge the supports from the National Natural Science Foundation of China (42104110, 41974123, 42174161, and 12334019), the Natural Science Foundation of Jiangsu Province (BK20210379, BK20200021), the Postdoctoral Science Foundation of China (2022M720989), and the Fundamental Research Funds for the Central Universities (B210201032).
Corresponding Authors: Ba Jing (Email: jba@hhu.edu.cn)
E-mail: jba@hhu.edu.cn
About author: Zhang Lin received his Ph.D. degree in Exploration Geophysics from Hohai University in 2020, and is working as a lecturer in the School of Earth Sciences and Engineering, Hohai University, since 2020. His research interests are the elastic wave propagation theories of porous media and pore microstructure characterization.
Cite this article:
. Permeability Estimation of Shale Oil Reservoir with Laboratory-derived Data: A Case Study of the Chang 7 Member in Ordos Basin[J]. APPLIED GEOPHYSICS, 2024, 21(3): 440-455.
2024, Vol. 21 
