General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures
Pre-existing natural fractures and other structurally weak planes are usually well-developed in unconventional reservoirs. When such fractures intersect with hydraulic induced fractures, they will redirect and propagate as an important mechanical principle of volume fracturing by the formation of co...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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KeAi Communications Co., Ltd.
2019-09-01
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| Series: | Petroleum |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2405656117301311 |
| _version_ | 1819162840707104768 |
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| author | Zhifeng Luo Nanlin Zhang Liqiang Zhao Fei Liu Nianyin Li |
| author_facet | Zhifeng Luo Nanlin Zhang Liqiang Zhao Fei Liu Nianyin Li |
| author_sort | Zhifeng Luo |
| collection | DOAJ |
| description | Pre-existing natural fractures and other structurally weak planes are usually well-developed in unconventional reservoirs. When such fractures intersect with hydraulic induced fractures, they will redirect and propagate as an important mechanical principle of volume fracturing by the formation of complex fracture networks. Under the shadow effect of natural fractures and other structurally weak planes with hydraulic supported fracture stress, hydraulic fractures do not fully propagate in the direction of the maximum horizontal-principal-stress. This paper computed the stress intensity factors of hydraulic fracture types I and II by integrating the various interactions, established universally-applicable mechanical principles for the propagation behavior when a hydraulic fracture propagating in an arbitrary direction intersects with a natural fracture at an arbitrary angle, and demonstrated the mechanical principles of the intersection between hydraulic induced fractures and pre-existing natural fractures. This study proved the following conclusions: as the intersection angle between the hydraulic fracture and the maximum horizontal-principal-stress increased, the possibility of the hydraulic fracture being captured by the natural fracture with an identical approaching angle first increased and then decreased; as the net stress increased, the intersection behavior between the hydraulic fracture and the natural fracture transitioned from penetration to capture. Keywords: Hydraulic induced fracture, Pre-existing natural fracture, Intersection criterion, Stress intensity factor, Extended finite element method |
| first_indexed | 2024-12-22T17:34:38Z |
| format | Article |
| id | doaj.art-537fc7adaaad4431b19da23e8ccb364f |
| institution | Directory Open Access Journal |
| issn | 2405-6561 |
| language | English |
| last_indexed | 2024-12-22T17:34:38Z |
| publishDate | 2019-09-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | Petroleum |
| spelling | doaj.art-537fc7adaaad4431b19da23e8ccb364f2022-12-21T18:18:31ZengKeAi Communications Co., Ltd.Petroleum2405-65612019-09-0153315320General criterion for intersection between hydraulic induced fractures and pre-existing natural fracturesZhifeng Luo0Nanlin Zhang1Liqiang Zhao2Fei Liu3Nianyin Li4State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, ChinaState Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, ChinaState Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, China; Corresponding author.Engineering Technology Research Institute of Southwest Oil & Gas Field Company, PetroChina, Guanghan, 618300, ChinaState Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, ChinaPre-existing natural fractures and other structurally weak planes are usually well-developed in unconventional reservoirs. When such fractures intersect with hydraulic induced fractures, they will redirect and propagate as an important mechanical principle of volume fracturing by the formation of complex fracture networks. Under the shadow effect of natural fractures and other structurally weak planes with hydraulic supported fracture stress, hydraulic fractures do not fully propagate in the direction of the maximum horizontal-principal-stress. This paper computed the stress intensity factors of hydraulic fracture types I and II by integrating the various interactions, established universally-applicable mechanical principles for the propagation behavior when a hydraulic fracture propagating in an arbitrary direction intersects with a natural fracture at an arbitrary angle, and demonstrated the mechanical principles of the intersection between hydraulic induced fractures and pre-existing natural fractures. This study proved the following conclusions: as the intersection angle between the hydraulic fracture and the maximum horizontal-principal-stress increased, the possibility of the hydraulic fracture being captured by the natural fracture with an identical approaching angle first increased and then decreased; as the net stress increased, the intersection behavior between the hydraulic fracture and the natural fracture transitioned from penetration to capture. Keywords: Hydraulic induced fracture, Pre-existing natural fracture, Intersection criterion, Stress intensity factor, Extended finite element methodhttp://www.sciencedirect.com/science/article/pii/S2405656117301311 |
| spellingShingle | Zhifeng Luo Nanlin Zhang Liqiang Zhao Fei Liu Nianyin Li General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures Petroleum |
| title | General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures |
| title_full | General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures |
| title_fullStr | General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures |
| title_full_unstemmed | General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures |
| title_short | General criterion for intersection between hydraulic induced fractures and pre-existing natural fractures |
| title_sort | general criterion for intersection between hydraulic induced fractures and pre existing natural fractures |
| url | http://www.sciencedirect.com/science/article/pii/S2405656117301311 |
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