WASHINGTON (AP) — The controversial practice of hydraulic fracturing to extract natural gas does not pose a high risk for triggering earthquakes large enough for humans to feel. But other types of energy-related drilling can make the ground noticeably shake. That's according to a report released late this week from the National Research Council.
The report concluded that large enough to be an issue are very rare. In more than 90 years of monitoring, human activity has been shown to trigger only 154 quakes, most of them moderate or small, and only 60 of them in the United States. That's compared to a global average of about 14,450 earthquakes of magnitude 4.0 or greater every year.
The study did find a small 2.3 magnitude earthquake in Oklahoma may have been linked to fracking, as well as a tremor in the United Kingdom.
The report commissioned by Congress and the U.S. Department of Energy was released on Friday.