Nucleation and arrest of fluid-induced aseismic fault slip

Antoine B. Jacquey, & Robert C. Viesca

Published September 11, 2022, SCEC Contribution #12288, 2022 SCEC Annual Meeting Poster #145

Microseismicity associated with fluid pressurization in the subsurface occurs during fluid injection but can also trigger after injection shut-in. Understanding the extent and duration of the post-injection microseismicity is critical to limit the risk of fluid-induced seismicity and insure the safe utilization of the subsurface.

In this study, we investigated using theoretical and two-dimensional numerical techniques how aseismic slip on a fault evolves and stops after a fluid pressurization event at constant pressure. We found that the locking mechanisms controlling the arrest of aseismic slip is mechanically-driven and highly depends on the initial fault stress criticality and the pressurization duration. The absolute arrest time of fault aseismic slip after injection shut-in is proportional to the pressurization duration and increases significantly with the initial fault stress criticality. These results provide insights into the mechanics controlling the arrest of microseismicity after fluid pressurization as a first milestone towards induced seismicity mitigation strategies. We also present ongoing progress on the extension of the proposed model to three-dimensional aseismic rupture and more complex injection scenarios.

Key Words
aseismic slip, induced seismicity, friction

Citation
Jacquey, A. B., & Viesca, R. C. (2022, 09). Nucleation and arrest of fluid-induced aseismic fault slip. Poster Presentation at 2022 SCEC Annual Meeting.

Related Projects & Working Groups
Fault and Rupture Mechanics (FARM)