Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation
Abstract Whether hydraulic fractures could connect multiple gas zones in the vertical plane is the key to fracturing treatment to jointly exploit coalbed methane and tight sandstone gas through integrative hydraulic fracturing in tight sandstone–coal interbedded formations. Laboratory true triaxial...
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| Format: | Article |
| Language: | English |
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KeAi Communications Co., Ltd.
2019-01-01
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| Series: | Petroleum Science |
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| Online Access: | http://link.springer.com/article/10.1007/s12182-018-0297-z |
| _version_ | 1818916660625539072 |
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| author | Peng Tan Yan Jin Liang Yuan Zhen-Yu Xiong Bing Hou Mian Chen Li-Ming Wan |
| author_facet | Peng Tan Yan Jin Liang Yuan Zhen-Yu Xiong Bing Hou Mian Chen Li-Ming Wan |
| author_sort | Peng Tan |
| collection | DOAJ |
| description | Abstract Whether hydraulic fractures could connect multiple gas zones in the vertical plane is the key to fracturing treatment to jointly exploit coalbed methane and tight sandstone gas through integrative hydraulic fracturing in tight sandstone–coal interbedded formations. Laboratory true triaxial hydraulic fracturing experiments were conducted on layered specimens with different combination types of natural sandstone and coal to simulate the propagation behavior of hydraulic fractures. The effects of the fracture initiation position, fracturing fluid viscosity and injection rate were discussed. The results showed that different fracture morphologies could be found. When initiating from coal seams, three patterns of fracture initiation and propagation were obtained: (1) The main hydraulic fracture initiated and propagated along the natural fractures and then diverged due to the effects of in situ stress and formed secondary fractures. (2) The hydraulic fracture initiated and propagated in the direction of the maximum horizontal stress. (3) Multiple fractures initiated and propagated at the same time. With the same fracturing fluid viscosity and injection rate, the hydraulic fractures initiating in sandstones had greater chances than those in coal seams to penetrate interfaces and enter neighboring layers. Excessively small or large fracturing fluid viscosity and injection rate would do harm to the vertical extension height of the induced fracture and improvement of the stimulated reservoir volume. Compared with operation parameters (fracturing fluid viscosity and injection rate), the natural weak planes in coals were considered to be the key factor that affected the fracture propagation path. The experimental results would make some contributions to the development of tight sandstone–coal interbedded reservoirs. |
| first_indexed | 2024-12-20T00:21:42Z |
| format | Article |
| id | doaj.art-feadfb27dafa47928a6e9b47baba4ac9 |
| institution | Directory Open Access Journal |
| issn | 1672-5107 1995-8226 |
| language | English |
| last_indexed | 2024-12-20T00:21:42Z |
| publishDate | 2019-01-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | Petroleum Science |
| spelling | doaj.art-feadfb27dafa47928a6e9b47baba4ac92022-12-21T20:00:10ZengKeAi Communications Co., Ltd.Petroleum Science1672-51071995-82262019-01-0116114816010.1007/s12182-018-0297-zUnderstanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigationPeng Tan0Yan Jin1Liang Yuan2Zhen-Yu Xiong3Bing Hou4Mian Chen5Li-Ming Wan6State Key Laboratory of Petroleum Resources and Engineering, China University of PetroleumState Key Laboratory of Petroleum Resources and Engineering, China University of PetroleumCNPC Engineering Technology R&D Company LimitedSINOPEC Shanghai Offshore Oil & Gas CompanyState Key Laboratory of Petroleum Resources and Engineering, China University of PetroleumState Key Laboratory of Petroleum Resources and Engineering, China University of PetroleumState Key Laboratory of Petroleum Resources and Engineering, China University of PetroleumAbstract Whether hydraulic fractures could connect multiple gas zones in the vertical plane is the key to fracturing treatment to jointly exploit coalbed methane and tight sandstone gas through integrative hydraulic fracturing in tight sandstone–coal interbedded formations. Laboratory true triaxial hydraulic fracturing experiments were conducted on layered specimens with different combination types of natural sandstone and coal to simulate the propagation behavior of hydraulic fractures. The effects of the fracture initiation position, fracturing fluid viscosity and injection rate were discussed. The results showed that different fracture morphologies could be found. When initiating from coal seams, three patterns of fracture initiation and propagation were obtained: (1) The main hydraulic fracture initiated and propagated along the natural fractures and then diverged due to the effects of in situ stress and formed secondary fractures. (2) The hydraulic fracture initiated and propagated in the direction of the maximum horizontal stress. (3) Multiple fractures initiated and propagated at the same time. With the same fracturing fluid viscosity and injection rate, the hydraulic fractures initiating in sandstones had greater chances than those in coal seams to penetrate interfaces and enter neighboring layers. Excessively small or large fracturing fluid viscosity and injection rate would do harm to the vertical extension height of the induced fracture and improvement of the stimulated reservoir volume. Compared with operation parameters (fracturing fluid viscosity and injection rate), the natural weak planes in coals were considered to be the key factor that affected the fracture propagation path. The experimental results would make some contributions to the development of tight sandstone–coal interbedded reservoirs.http://link.springer.com/article/10.1007/s12182-018-0297-zHydraulic fracturingFracture propagationSandstone–coal interbedLayered formation |
| spellingShingle | Peng Tan Yan Jin Liang Yuan Zhen-Yu Xiong Bing Hou Mian Chen Li-Ming Wan Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation Petroleum Science Hydraulic fracturing Fracture propagation Sandstone–coal interbed Layered formation |
| title | Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation |
| title_full | Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation |
| title_fullStr | Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation |
| title_full_unstemmed | Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation |
| title_short | Understanding hydraulic fracture propagation behavior in tight sandstone–coal interbedded formations: an experimental investigation |
| title_sort | understanding hydraulic fracture propagation behavior in tight sandstone coal interbedded formations an experimental investigation |
| topic | Hydraulic fracturing Fracture propagation Sandstone–coal interbed Layered formation |
| url | http://link.springer.com/article/10.1007/s12182-018-0297-z |
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