Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs
In karstic-fractured carbonate reservoirs, most of the oil resources are hosted in vugs. Connecting as many vugs as possible by hydraulic fracturing is the key to achieving effective development. However, the interaction mechanism between vugs and hydraulic fractures is complicated and has not been...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/15/20/7661 |
| _version_ | 1827650447786115072 |
|---|---|
| author | Lei Wang Xiaolong Wu Longfei Hou Yintong Guo Zhenhui Bi Hanzhi Yang |
| author_facet | Lei Wang Xiaolong Wu Longfei Hou Yintong Guo Zhenhui Bi Hanzhi Yang |
| author_sort | Lei Wang |
| collection | DOAJ |
| description | In karstic-fractured carbonate reservoirs, most of the oil resources are hosted in vugs. Connecting as many vugs as possible by hydraulic fracturing is the key to achieving effective development. However, the interaction mechanism between vugs and hydraulic fractures is complicated and has not been fully revealed. In this study, both experimental and numerical simulations were implemented to investigate the interaction between vugs and hydraulic fractures. Key factors, such as vug size, horizontal stress difference, and the internal pressure of the vug, were considered. The results showed that the vug played an important role in the propagation of hydraulic fractures. Three interaction modes of vugs and hydraulic fractures were observed: crossing, arresting, and bypassing. Owing to the variation of the stress concentration existing around the vug, the hydraulic fracture could be arrested by a small vug but would bypass a vug with a larger size. Whether the hydraulic fracture could communicate with the vug was mainly controlled by the horizontal stress difference. Under large horizontal stress differences (≥20 MPa), the hydraulic fracture could cross and connect multiple vugs. The difference between the horizontal minimum stress and the internal pressure of the vug was also particularly significant for fracture propagation. The smaller the difference, the easier the fracture communicated with the vug. The above findings would be valuable and constructive for the optimal design of field hydraulic fracturing in karstic-fractured carbonate reservoirs. |
| first_indexed | 2024-03-09T20:16:21Z |
| format | Article |
| id | doaj.art-430fc6f84e1a4c5682773c904e78a0ed |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-09T20:16:21Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-430fc6f84e1a4c5682773c904e78a0ed2023-11-23T23:58:31ZengMDPI AGEnergies1996-10732022-10-011520766110.3390/en15207661Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate ReservoirsLei Wang0Xiaolong Wu1Longfei Hou2Yintong Guo3Zhenhui Bi4Hanzhi Yang5State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, ChinaState Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, ChinaGuangzhou Expressway Co., Ltd., Guangzhou 510290, ChinaState Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, ChinaState Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, ChinaState Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, ChinaIn karstic-fractured carbonate reservoirs, most of the oil resources are hosted in vugs. Connecting as many vugs as possible by hydraulic fracturing is the key to achieving effective development. However, the interaction mechanism between vugs and hydraulic fractures is complicated and has not been fully revealed. In this study, both experimental and numerical simulations were implemented to investigate the interaction between vugs and hydraulic fractures. Key factors, such as vug size, horizontal stress difference, and the internal pressure of the vug, were considered. The results showed that the vug played an important role in the propagation of hydraulic fractures. Three interaction modes of vugs and hydraulic fractures were observed: crossing, arresting, and bypassing. Owing to the variation of the stress concentration existing around the vug, the hydraulic fracture could be arrested by a small vug but would bypass a vug with a larger size. Whether the hydraulic fracture could communicate with the vug was mainly controlled by the horizontal stress difference. Under large horizontal stress differences (≥20 MPa), the hydraulic fracture could cross and connect multiple vugs. The difference between the horizontal minimum stress and the internal pressure of the vug was also particularly significant for fracture propagation. The smaller the difference, the easier the fracture communicated with the vug. The above findings would be valuable and constructive for the optimal design of field hydraulic fracturing in karstic-fractured carbonate reservoirs.https://www.mdpi.com/1996-1073/15/20/7661carbonate reservoirvughydraulic fracture propagationphysical simulationXFEM model |
| spellingShingle | Lei Wang Xiaolong Wu Longfei Hou Yintong Guo Zhenhui Bi Hanzhi Yang Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs Energies carbonate reservoir vug hydraulic fracture propagation physical simulation XFEM model |
| title | Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs |
| title_full | Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs |
| title_fullStr | Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs |
| title_full_unstemmed | Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs |
| title_short | Experimental and Numerical Investigation on the Interaction between Hydraulic Fractures and Vugs in Fracture-Cavity Carbonate Reservoirs |
| title_sort | experimental and numerical investigation on the interaction between hydraulic fractures and vugs in fracture cavity carbonate reservoirs |
| topic | carbonate reservoir vug hydraulic fracture propagation physical simulation XFEM model |
| url | https://www.mdpi.com/1996-1073/15/20/7661 |
| work_keys_str_mv | AT leiwang experimentalandnumericalinvestigationontheinteractionbetweenhydraulicfracturesandvugsinfracturecavitycarbonatereservoirs AT xiaolongwu experimentalandnumericalinvestigationontheinteractionbetweenhydraulicfracturesandvugsinfracturecavitycarbonatereservoirs AT longfeihou experimentalandnumericalinvestigationontheinteractionbetweenhydraulicfracturesandvugsinfracturecavitycarbonatereservoirs AT yintongguo experimentalandnumericalinvestigationontheinteractionbetweenhydraulicfracturesandvugsinfracturecavitycarbonatereservoirs AT zhenhuibi experimentalandnumericalinvestigationontheinteractionbetweenhydraulicfracturesandvugsinfracturecavitycarbonatereservoirs AT hanzhiyang experimentalandnumericalinvestigationontheinteractionbetweenhydraulicfracturesandvugsinfracturecavitycarbonatereservoirs |