Reflection-seismic survey and drill core data suggest that a hydraulic fracturing well responsible for induced earthquakes in southern Alberta, Canada, in December 2011 was in contact with a hydraulically and seismically active fault, where past fluid-flow dissolved rock strata underlying the target gas reservoir, causing a collapse of the resulting cavity; the results suggest that induced seismicity requires a coincidence of multiple geologic conditions that are rarely expected to occur, according to the authors.
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Article #18-07549: "Faults and associated karst collapse suggest conduits for fluid flow that influence hydraulic fracturing-induced seismicity," by Elwyn Galloway, Tyler Hauck, Hilary Corlett, Dinu Pana, and Ryan Schultz.
MEDIA CONTACT: Ryan Schultz, Alberta Geological Survey, Edmonton, CANADA; e-mail: Ryan.Schultz@aer.ca ; Jordan Fitzgerald, Alberta Geological Survey, Edmonton, CANADA: e-mail: media@aer.ca
Proceedings of the National Academy of Sciences