States like Alaska and California frequently experience tremors that disrupt drivers and wreak chaos on homes and businesses. Central U.S. states rarely experience earthquakes, but experts suggest that fracking might be the cause of earthquakes in previously stable states.
From Environmental to Human
In most cases, earthquakes occur because of the shifting of tectonic plates that occurs naturally. Certain U.S. states contain fault lines around which the earth is more likely to move. However, human causes of earthquakes sometimes surface, and fracking represents one of the most-reported causes in recent years.
In the oil and gas industry, oil and other materials are extracted from the earth, after which waste water is injected back into the earth, causing disruptions. According to Reuters, 95 percent of the water extracted through fracking finds its way back into underground rock formations to preserve the appropriate pressure.
From Earthquakes to Sinkholes
In addition to earthquakes, sinkholes and other phenomena have been linked to fracking. For example, a Ceres report suggests that the vast quantities of fresh water required for fracking has increased water stress in drought-prone areas.
However, fracking also brings tremendous benefits to the environment and to consumers’ wallets. The Brookings Institute revealed that the increased practice of hydraulic fracturing has resulted in natural gas price drops of nearly 50 percent compared to the estimated price if drilling continued without the benefit of fracking.
From Undetectable to Devastating
Initially, fracking caused only small earthquakes in states like Oklahoma and Texas, with most tremors rating a 2.8 magnitude on the Richter scale. By contrast, “natural” earthquakes in states like California sometimes exceed 7.0 on the Richter scale.
However, earthquakes of increasing intensity are causing concern among residents of the affected states as well as researchers and oil and gas industry leaders. Some experts contend that the greater magnitude suggests fault-line involvement rather than tremors induced by fracking.
Brian Stump, a geophysicist with Southern Methodist University, agrees with fellow SMU professor Heather DeShon when she says, “In order to have an earthquake with the size 3.6 magnitude, there has to be a fault,” according to CNN.
Several of the recent earthquakes in Oklahoma and Texas have leveled homes and wrought considerable destruction on businesses and public infrastructures. Crumbling walls, broken roads, and downed power lines contribute to the anxiety over increased earthquake activity.
Earthquakes under magnitude 2.0 are not registered above ground. People do not feel the tremors or notice any disruptions in their environment. Damage to buildings and other structures remains unlikely until an earthquake reaches a magnitude of 5.0.
From Extraction to Injection
Induced earthquakes result from changes in the pressure in the earth’s subsurface. Earthquakes rarely result from the extraction of water and oil that occurs during fracking, but the injection of water back into the wells can result in disruptions.
The U.S. Geological Survey fuels speculation that fracking is responsible for “induced seismicity.” The reported earthquakes correspond with the locations of fracking activity, suggesting links between the two events. However, the debate still rages on two fronts. First, experts disagree over whether or not the earthquakes would occur even without the introduction of fracking; secondly, researchers argue over the benefits and drawbacks of fracking.
Understanding the impact of the oil and gas industry on the environment helps businesses and government bodies make crucial decisions about future activity.
Information sourced from Reuters, CNN and Ceres
