loading page

Stress chatter on a fracture network reactivated by hydraulic fracturing
  • +5
  • Andrés Felipe Peña Castro,
  • Marco P Roth,
  • Alessandro Verdecchia,
  • John Onwuemeka,
  • Yajing Liu,
  • Rebecca M. Harrington,
  • Yong Zhang,
  • Honn Kao
Andrés Felipe Peña Castro
McGill University
Author Profile
Marco P Roth
Ruhr University Bochum
Author Profile
Alessandro Verdecchia
McGill University
Author Profile
John Onwuemeka
McGill University
Author Profile
Yajing Liu
McGill University

Corresponding Author:[email protected]

Author Profile
Rebecca M. Harrington
Ruhr University Bochum
Author Profile
Yong Zhang
Peking University
Author Profile
Honn Kao
Geological Survey of Canada
Author Profile

Abstract

Source processes of injection induced earthquakes involve complex fluid-rock interaction often elusive to regional seismic monitoring. Here we combine observations from a local seismograph array in the Montney basin, northeast British Columbia, and stress modeling to examine the spatial and temporal evolution of the 30 November 2018 M 4.5 hydraulic fracturing induced earthquake sequence. The mainshock occurred at ~ 4.5 km in the crystalline basement two days following injection at ~ 2.5 km, suggesting direct triggering by rapid fluid pressure increase via a high-permeability conduit. Most of the aftershocks are located in the top 2 km sedimentary layers, with focal mechanisms indicating discrete slip along sub-vertical surfaces in a ~ 1 km wide deformation zone. Aftershock distribution is also consistent with static stress triggering from the M 4.5 coseismic slip. Our analysis suggests complex hydraulic and stress transfer between fracture/fault networks needs to be considered in induced seismic hazard assessment.