Annual hazard map includes human-caused tremors for first time
Northern Oklahoma is just as susceptible to a damaging earthquake within the next year as the most quake-prone areas of California. That’s because earthquakes are no longer just a natural hazard, the U.S. Geological Survey says. In its new quake hazards forecast released March 28, the agency for the first time has included artificially triggered seismicity.
An increased risk in the central United States largely stems from sites where fluids, such as wastewater from fracking, are injected underground (SN: 8/9/14, p. 13). Rising fluid pressure underground can unclamp faults and unleash earthquakes (SN: 7/11/15, p. 10). From 1973 to 2008, an average of 24 potentially damaging