Online Material: Lists of earthquake locations and focal depths in the vicinity of the Stoney Creek Oil and Gas Field, interpretation of sonic log of velocities, velocity model, and events used in the velocity inversion. In recent years, there has been much interest in seismicity induced by hydrocarbon operations (e.g., Jones et al. , 2014). In the United States, it is mainly the reinjection of waste water that caused a major increase in the number of recorded earthquakes (Ellsworth, 2013). In contrast, lower magnitude earthquakes induced by hydraulic fracturing (HF) of tight reservoirs has attracted less interest. However, HF in western Canada has been associated with earthquakes of moderate magnitudes and more frequent occurrences. Three magnitude 3.5–3.6 events occurred in northeast British Columbia in 2010–2011 and a magnitude 4.4 in northern Alberta in January 2015. Both regions were only weakly seismic prior to the start of HF operations (see other articles in this issue; BC Oil and Gas Commission, 2012). In eastern Canada, HF for shale gas has occurred only at an exploratory‐scale in Quebec and New Brunswick. In the St. Lawrence Valley, multistage, slickwater HF of the Utica shale was done in 19 of the 29 wells drilled (Lavoie et al. , 2014). During that time period, very few earthquakes were detected in the surrounding areas. Although some of these earthquakes were shallow and within 10 km of wells, the hundreds of days between HF and the earthquakes rendered a causative link unlikely (Lamontagne and Ma, 2014). Since 2009, some HF has been conducted in southeast New Brunswick and is the topic of this article. In many areas worldwide, natural seismicity is only recorded at regional distances before hydraulic activity started. For example, in northeast British Columbia, the Canadian National Seismograph Network had very sparse coverage before mid‐2013, years after HF …