Anisotropic Brittleness Characterization and Analysis of VTI Media
Qiyu 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 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 authorJinming Cui
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 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 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 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 authorJinming Cui
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 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: This research was supported by the R&D Department of China National Petroleum Corporation (2022DQ0604-04).
ABSTRACT
The brittleness index is a crucial parameter for evaluating the brittleness of subsurface reservoirs. Accurate brittleness determination optimizes fracture design and guides oil and gas extraction, especially in shale formations. Traditionally, the brittleness index assumes isotropy, which fails to capture the anisotropic nature of shale reservoirs and often leads to prediction errors. To mitigate this challenge, this study introduces a stiffness coefficient matrix specifically designed for anisotropic media and proposes a brittleness index equation tailored for transverse isotropic (VTI) media. Experimental results show that the proposed anisotropic brittleness index provides a more accurate assessment of shale reservoir brittleness than the conventional isotropic brittleness index. Ultimately, the anisotropic brittleness index is applied to field logging data, thereby validating the effectiveness of the method in distinguishing between reservoirs of high and low brittleness.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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