Seismic Hazard and Hydraulic Fracture-induced Seismicity

Abstract

Traditionally, to relate the seismic hazard potential in seismically active areas, empirical ground motion prediction equations (EGMPE) are used to relate event parameters like magnitude and location to site characteristics such as peak ground acceleration (PGA) or peak ground velocity (PGV) which tend to be how building codes are parametrized. There are some key differences between induced and natural seismicity – induced earthquakes tend to be shallower and to release less stress – which affect peak ground motions. Standard EGMPE derived from natural earthquakes may not be appropriatly applied to predict the ground motion generated by induced earthqakes. In this study we develop a new EGMPE specific for hydraulic fracture stimulations in the Horn River basin using PGV and PGA measurements resulting from Mw0.2 to Mw2.9 induced seismic events locally recorded over a two-year period. The strongest recorded PGA of 0.017g was obtained for the largest magnitude event in the dataset and corresponds to the lowest PGA range introduced in the 2014 USGS seismic hazard map for 2475 year return period and could only be felt by a few people. The EGMPE developed in this study can be extrapolated for similar larger magnitude events and included into future Probabilistic Seismic Hazard Analysis.