Fracking Earthquakes

My prediction last September of a major earthquake in California has not yet come to pass, but it has caused me to learn quite a bit more about temblors.  While I am still far from being an expert, I have learned enough to know that the people who claim to be experts are full of it.

Nobody understands earthquakes well enough, and some of the theories out there, while they may actually contain a grain of truth, are presented in such a way that they are easy to dismiss.

Last week, for example, numerous news sources published stories saying that fracking – the hydraulic fracturing process used to extract oil and gas from the earth – was responsible for an increase in earthquakes in the Midwest.  This excerpt from Discovery is fairly typical:

Man-made earthquakes are real, they are proliferating across the U.S. Midwest, and the oil and gas industry is "almost certainly" responsible. Those are the latest conclusions scientists with the U.S. Geological Survey will be discussing at a seismology conference next week. Their more reassuring message: none of the man-made tremors have been big enough to knock down any buildings -- so far.

The nation’s midsection is typically quiet, geologically speaking. USGS seismologist Bill Ellsworth noticed an unusual number of earthquakes in that region (beginning) about 12 years ago, he wanted to know why.

Ellsworth and his colleagues watched the number of quakes jump from a steady background of 20 tremors a year to 50 in 2009, 87 in 2011 and a whopping 134 last year. Clearly, something strange was going on.

That's where the oil and gas industry comes in. From experiences with dams, scientists know that one man-made way to unlock a fault is to lubricate it. In the past year, several studies have blamed a natural-gas-extraction technique known as fracking for quakes. That process requires prospectors to pump billions of gallons of water a year deep underground. Forced underground under high pressure, the water cracks open the rocks and releases natural gas trapped in small pockets within them.

But Ellsworth's closer inspection revealed that many of the new quakes were clustering not around the drilling sites but instead around wastewater wells, the much deeper holes where companies dump the salty frack water once it has been used.

“Waste wells have been around for decades. There are tens of thousands of waste wells in the country, but very few quakes,” NPR’s Christopher Joyce explained in his interview with Ellsworth. “What's changed is that the gas industry is using—and disposing of—more water. Waste wells are often deeper than gas drilling wells, down into basement rock where faults are more common.”

Meanwhile, the U.S. Interior Department (DOI) is contradicting media reports on a government study that supposedly tied natural gas drilling and fracking to a rise in earthquakes.

"There is no evidence to suggest that hydraulic fracturing itself is the cause of the increased rate of earthquakes," Interior Department Deputy Secretary David Hayes wrote. Hayes does believe that a rise in minor earthquakes is "man-made," but added that "it remains to be determined if they are related to either changes in production methodologies or to the rate of oil and gas production."

Commenting on reports that an Interior Department study had found a connection between fracking and earthquakes, Hayes said "the accuracy of these media reports varied greatly."