Human-induced earthquakes will put 3 million Americans at risk in 2017. A recent statement from the U.S. Geological Survey (USGS) predicts man-made earthquakes, particularly in Oklahoma and Kansas, are likely to affect people who live in states with corresponding oil fracking operations that inject wastewater into the ground.
While the number of people in danger of human-induced earthquakes could be considered staggering, the figure is actually less than two years ago. Per the USGS, a higher number of earthquakes occurred in 2015, which potentially put 7 million people at risk. Additionally, fewer earthquakes were felt in 2016 than 2015.
“The good news is that the overall seismic hazard for this year is lower than in the 2016 forecast, but despite this decrease, there is still a significant likelihood for damaging ground shaking in the U.S. in the year ahead,” said Mark Petersen, chief of the USGS National Seismic Hazard Mapping Project, as cited by USA Today.
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Texas, Arkansas, Colorado, Kansas, and Oklahoma saw the greatest escalation in human-induced earthquakes. In 2013, 109 earthquakes with a magnitude of three or higher were recorded in Oklahoma alone. A tremor of that power will cause things to shake but usually does not result in much damage. One year later, 585 quakes of the same magnitude were felt, and 906 were documented in 2015.
In early 2016, 70 small earthquakes rattled Oklahoma residents over a seven-day period. Later in the year, a 5.6-magnitude quake, the largest recorded in the state’s history, rocked Pawnee, Oklahoma, prompting many citizens to protest against fracking operations.
According to a Popular Science report, studies have definitively connected wastewater injection with a surge in human-induced earthquake activity in a specific area. As part of the fracking procedure, oil is pumped out from deep within the earth. As the oil comes to the surface, salty, polluted water rides along with it. This wastewater is later separated from the oil and injected back into the ground deep enough that water supplies are not contaminated.
In 2016, new rules were enacted by state regulators that put tighter restrictions on wastewater disposal. These new regulations caused a drop in natural gas and oil production, which corresponded with less wastewater being injected into the ground and a reduced number of human-induced earthquakes.
While scientists have noted that 2016 did have fewer human-induced earthquakes, it will still take a while before the number settles to a normal rate. With the amount of injected wastewater already sitting deep in the ground, seismologists think it may be up to 10 years before the number of earthquakes falls to natural levels.
“I think it’s really important to understand that this triggering process cannot be switched off. If the probability of a damaging earthquake is decreasing right now, it doesn’t mean that it’s low. It’s still high, and there might be damaging earthquakes in Oklahoma over the next few years,” said Cornelius Langenbruch, co-author of a 2016 study to understand the increased amount of human-induced earthquakes in Oklahoma, as cited by Popular Science. “You really have to be patient, and be aware that this is not the end of induced earthquakes. It will take some time before it gets back down to the background rate.”
Energy in Depth, a research and education group founded by the Independent Petroleum Association of America, believes the lower number of human-induced earthquakes is an assertive sign that cooperative efforts by scientists, regulators, and fracking operation companies are working. However, millions of people are still at risk of suffering a damaging earthquake, and their chances may increase or decrease depending on how the fracking industry implements new techniques.
The USGS report, published in Seismological Research Letters, predicts a total of 4 million people are at risk from both natural and human-induced earthquakes in 2017. As new research continues to cement the connection between fracking and human-induced earthquakes, seismologists can use improved data to more accurately predict where and when the next time the ground decides to rumble.
[Featured Image by Justin Sullivan/Getty Images]