The Finite-conductivity Fracture Networks Model in Shale Gas Reservoirs with Consideration of Induced Fractures

doi:10.11885/j.issn.1674-5086.2019.09.17.06

Abstract

Abstract: In order to analyze the influence of secondary induced fractures on the pressure response of shale gas wells, a finite conductivity fracture network flow model of shale gas reservoir with coupling multiple migration mechanism has been established, and the pressure dynamic characteristics have been studied. Firstly, the analytical solution of pressure in shale gas reservoir has been obtained by employing Laplace space source function, local coordinate transformation and superposition principle. Then, based on the finite difference method and the flow distribution transformation of intersection element, the numerical solution of fracture element has been derived. By coupling the flow of gas reservoir and fracture, the pressure response curve considering the influence of secondary fracture was drawn, and the influences of characteristic parameters (such as the number of secondary fracture groups, secondary fracture angle, and fracture conductivity, etc.) were analyzed. The results show that there are 10 typical flow stages, which can effectively characterize the influence of secondary fractures. In addition, the presented model will be helpful for understanding the transient performance of multi-stage fractured horizontal wells with consideration of induced fractures.

Key words: shale gas reservoir, secondary induced fractures, fractured horizontal well, finite-conductivity, pressure performance

CLC Number:

TE312

FANG Quantang, LI Zhenglan, DUAN Yonggang, WEI Mingqiang, ZHANG Yuyi. The Finite-conductivity Fracture Networks Model in Shale Gas Reservoirs with Consideration of Induced Fractures[J]. 西南石油大学学报(自然科学版), 2019, 41(6): 139-145.

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URL: http://journal15.magtechjournal.com/Jwk_xnzk/EN/10.11885/j.issn.1674-5086.2019.09.17.06

http://journal15.magtechjournal.com/Jwk_xnzk/EN/Y2019/V41/I6/139

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