Investigating triggering mechanisms behind hydraulic fracturing-induced seismicity: Elastic stress transfer

Kettlety, Tom (School of Earth Sciences, University of Bristol) | Verdon, James P. (School of Earth Sciences, University of Bristol) | Werner, Maximilian (School of Earth Sciences, University of Bristol) | Kendall, J Michael (School of Earth Sciences, University of Bristol)

OnePetro 

In this study we investigate the potential driving mechanisms that lead to induced seismicity during hydraulic fracturing. Fluid processes (pore-pressure changes and poroelastic effects) are often considered to be the primary driver. However, some studies have suggested that elastic deformation, and the resulting stress interactions, may contribute to further seismicity. In this paper we use a dataset acquired during hydraulic fracturing to calculate elastic stress transfer during a period of fault activation and induced seismicity. We find that elastic stresses may have weakly promoted failure during the initial phase of activity. However, at later times, stress changes generally acted to inhibit further slip. These signals are further weakened once uncertainties in source mechanisms and other geomechanical parameters are taken into account. Given the estimated in situ stress field, relatively large increases in pore pressure are required to reach the Mohr-Coulomb failure envelope for these faults. We therefore hypothesise that in such scenarios the relatively smaller scale elastic stress transfer effects do not play a significant role.

Presentation Date: Tuesday, October 16, 2018

Start Time: 1:50:00 PM

Location: 208A (Anaheim Convention Center)

Presentation Type: Oral