Tuesday, March 10, 2015

Increasing Earthquakes in Oklahoma Now Tied To Frack Wells

As a matter of geological history, before 2008 Oklahoma had only one or two Richter scale 3 earthquakes each year. But last year hundreds were counted, and though it was only hinted at in the mainstream media, many of us suspected the increasing frequency of fracking -especially via frack disposal wells. As one geophysicist  (Katie Keranen) at Cornell University put it: "We've never seen anything like this before."

Here's a brief recap of the frack process: To get oil and gas out of the ground, drilling engineers have to pump out water - as well as inject it. (As they do here in Colo., consuming 4 million gallons of water with each well injection - one of the reasons we're running low on water.)  While the injected water is fresh - usually taken from what would normally have gone to crops - the effluent, pumped out liquid is more like brine.  This stuff is toxic to the environment so the frack companies get rid of it by injecting it into rocks via what are called "disposal wells".

While some geoscientists have suggested that such wastewater dumping could set off quakes, including the ones in OK as well as TX, there was one problem: most wells were too far away from the actual site of earthquakes. In the case of the Sooner state, most wells - especially disposal - were too distant from what has been called the "Jones swarm" of quakes. Thus people, especially oil and gas outfits, declared the wells were too distant to cause the quakes.

But give Keranen credit, she didn't buy into the simplistic argument and decided to test her hypothesis: that distant disposal wells could cause quakes - using a computer model. Her team at Cornell devised a model to estimate how far wastewater travels underground, and the pressure created around 89 wells. (Too much pressure would be able to stress the faults running throughout the Earth's crust in a frack region like OK.)

The Cornell team analyzed ground movement to pinpoint the origin of thousands of the Jones' swarm earthquakes occurring from 2010 to 2013. The computer simulation found that the magnitude of the pressures spreading from the wells to the quake origin sites were large enough to trigger the earthquakes.

Incredibly, the primary culprits were four high volume disposal wells. This alone, Keranen believes, could help the oil and gas industry pinpoint problem wells and maybe avoid so many quakes in the future.  But is she realistic? I mean, even the 5.6 quake that jolted the state in 2011 (which scientists later linked to wastewater injections) drew barely a peep and certainly didn't prompt new regulations.

As here in Colorado, when the fossil fuel industry has its tentacles extended into state capitols,  there is little chance of containing the excesses of fracking - whether that affects soil, air, water quality or (as in the case of OK) earthquakes spawned by disposal wells.

How to test Keranen's hypothesis in the real world? Easy! Turn off the frickin' frack wells and see if the earthquakes stop! If they don't then we will know her computer simulation missed something.

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