Empirical Green’s Functions Analysis of Induced Earthquakes in the Duvernay Play Near Fox Creek, Alberta

Date: 4/25/2019

Time: 04:30 PM

Room: Cascade I

The rate of earthquakes in the Western Canadian Sedimentary Basin has increased significantly since 2010. The increase in seismicity rate is thought to be anthropogenic in origin due to strong spatial and temporal correlations between observed seismicity and hydraulic fracturing operations in the region. Some of the largest induced events attributed to hydraulic fracturing have occurred within the Duvernay play in the Fox Creek region of Alberta, Canada. In January 2016, a Mw 4.1 event was induced by a nearby hydraulic fracturing program which resulted in the cessation of injection, in line with the seismic hazard protocol, as the red-light threshold (ML >4) had been exceeded. A recent study showed that the moment tensor solution of this event contained significant non-double-couple components (~20%), and it was postulated that the non-double-couple component was either a manifestation of fracture growth or slip on non-coplanar faults (Wang et al., 2018). Through empirical Green’s function analysis we observe a complex spectral source signature for the Mw 4.1 event which may indicate simultaneous rupture along two fault strands, coherent with the latter model. Furthermore, high precision double-difference re-locations image two fault strands that were lit up immediately after the Mw 4.1 event occurred. The combined lateral extent of these two fault strands is ~ 1km, which is coherent with expected fault dimensions for a Mw 4 event.

Presenting Author: Megan Zecevic

Authors