EGU22-5614, updated on 10 Jan 2024
https://doi.org/10.5194/egusphere-egu22-5614
EGU General Assembly 2022
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Phase Field Modelling of Interactions Between Hydraulic Fractures and Natural Fractures

Xiaoxuan Li1,2,3, Hannes Hofmann3, Keita Yoshioka4,5, Yongjiang Luo1,2, and Yunpei Liang1,2
Xiaoxuan Li et al.
  • 1State Key Laboratory of Coal Mine Disaster Dynamics and Control, School of Resources and Safety Engineering, Chongqing University, Chongqing, China (lixiaoxuan1212@163.com, luoyj16@cqu.edu.cn, Liangyunpei@cqu.edu.cn)
  • 2School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China (lixiaoxuan1212@163.com, luoyj16@cqu.edu.cn, Liangyunpei@cqu.edu.cn)
  • 3Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, Germany (hannes.hofmann@gfz-potsdam.de)
  • 4Department of Environmental Informatics, Helmholtz Centre for Environmental Research‐UFZ, Leipzig, Germany (keita.yoshioka@ufz.de)
  • 5Department of Civil Engineering, University of Manitoba, Winnipeg, Canada (keita.yoshioka@ufz.de)

Hydraulic fracturing is widely applied in unconventional reservoirs to generate fracture networks for productivity enhancement. Interactions between hydraulic fractures and natural fractures have a great impact on fracture propagation. In this study, we use a two-dimensional phase field model to investigate interactions between hydraulic fractures and different frictional or cemented fractures under different in-situ stress, injection rate, natural fracture orientation and strength. We find that with the increasing stress anisotropy, hydraulic fracture is more likely to cross natural fracture and leads to a lower fracture complexity. A moderate injection rate is conducive for complex fractures. The approaching angle between the hydraulic fracture and natural fracture impact fracture topology. Complex fractures are formed when the angles are not so steep. With the increasing strength contrast between natural fractures and the rock matrix, the material heterogeneity increases for hydraulic fractures to generate complex fractures. Compared with frictional NFs, opening stronger cemented NFs requires more pressure than hydraulic fracture propagating outside the interface. The numerical investigations in this study can provide theoretical support and design guidance for fracturing operations in complex geological conditions.

How to cite: Li, X., Hofmann, H., Yoshioka, K., Luo, Y., and Liang, Y.: Phase Field Modelling of Interactions Between Hydraulic Fractures and Natural Fractures, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5614, https://doi.org/10.5194/egusphere-egu22-5614, 2022.

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