Numerical simulation of stress field reorientation in multi-fractures

Yan Deng, Shuxing Mu, Yuxuan Liu, Na Mu, Jianchun Guo, Jie Zeng, Hao Yu

Research output: Contribution to journalArticlepeer-review

Abstract

Understanding the stress state caused by a subsequent failure is crucial for successful refracturing. However, there are many differences between the stress reorientation phenomena of a multi-fracture horizontal well and that of a single fracture in a vertical well, including the interaction of multi-fractures. These factors can lead to a change in the stress field of multiple fractures, which is more complex than that of a single fracture. In this paper, based on the elastic theory of porous media and the mechanism of fluid–structure interaction, a finite element numerical model of multi-fracture stress fields is established. The net pressure loaded on the fracture wall was corrected using the fracture line model, which was solved using the separated coupling method with a staggered strategy, and a full coupling simulation of fluid flow and rock deformation was achieved. The results showed that with an increase in production time, the stress reorientation area around the fracture and at both ends first increased at a faster rate, then slowly decreased, and finally disappeared,indicating an optimal refracturing time window. This suggests that the greater the number of fractures, the greater the fracture inclination and fracture bending degree, and the more unfavorable it is for the formation and maintenance of the stress reorientation area near the fracture and at both ends of the fracture. The reorientation of the stress field between horizontal wells may lead to the fracture of the infill wells, causing bending and propagation towards the pressure-depletion area, thus reducing productivity.

Original languageEnglish
Article number36
JournalGeomechanics and Geophysics for Geo-Energy and Geo-Resources
Volume10
Issue number1
Early online dateJan 2024
DOIs
Publication statusPublished - Dec 2024

Fingerprint

Dive into the research topics of 'Numerical simulation of stress field reorientation in multi-fractures'. Together they form a unique fingerprint.

Cite this