New Slow-Moving Earthquake Discovered: A Fracking-Induced Phenomenon

A recent study has unveiled a novel type of earthquake in western Canada, attributed to hydraulic fracturing (fracking) activities. This newly identified seismic phenomenon, termed Earthquakes with Hybrid-frequency Waveforms (EHWs), exhibits slower shaking and prolonged durations compared to conventional earthquakes, indicating a significant shift in understanding human-induced seismic events. The findings, published in the journal *Nature Communications* on June 30, 2025, by a collaborative team from the Geological Survey of Canada, Ruhr-Universität Bochum, and McGill University, suggest that these quakes may help mitigate the risk of more damaging seismic occurrences.

The research team recorded seismic activity during fracking operations in the Montney Shale formation of British Columbia, where they observed approximately 350 earthquakes, with about ten percent demonstrating the distinctive characteristics of EHWs. Unlike typical earthquakes that are characterized by rapid rupture and swift energy release, EHWs are marked by a gradual onset and extended duration. For instance, a magnitude 1.5 standard earthquake typically dissipates in about seven seconds, whereas an EHW of similar magnitude can continue for over ten seconds, according to Rebecca Harrington, a professor at Ruhr-Universität Bochum.

The study challenges conventional theories surrounding fracking-induced earthquakes, which traditionally focused on direct fluid pressures causing fractures. Instead, it posits the role of aseismic slip—a slow, gradual movement along faults that does not release significant seismic energy—as a critical factor. This hypothesis is supported by laboratory experiments and computational models that indicate that fluids injected into fractured rock may not directly induce earthquakes but rather initiate a gradual shift in stress that can ultimately lead to a full seismic event.

Dr. Hongyu Yu, formerly of Ruhr-Universität Bochum and now at the Geological Survey of Canada, emphasized the importance of recognizing EHWs as indicators of evolving fault behavior, suggesting they may serve as precursors to larger seismic events. The implications of this research are significant, particularly for the energy extraction industry, as understanding these slow-slip signals could allow operators to adjust injection strategies, thereby reducing the likelihood of inducing more severe earthquakes.

The study’s findings provide rare field-based evidence that reinforces what had previously been largely theoretical and experimental knowledge about slow ruptures related to fluid injections. This new understanding of EHWs not only enhances the scientific community's grasp of fault dynamics but also informs safer drilling practices in the future.

As hydraulic fracturing continues to be a contentious issue due to its association with induced seismicity, this research highlights the complexity of the interactions between human activities and natural geological processes. The challenge now lies in developing reliable systems to detect these slow-slip events in real time, which could ultimately lead to improvements in the safety and predictability of fracking operations. The study underscores the necessity for ongoing research into the subtle dynamics of fault activity, particularly in areas like the Western Canada Sedimentary Basin, where significant fracking-related earthquakes have been observed.