Reply #2: Ban or minimize fracking and frequency of earthquakes drops drastically.

[Divernan]

Industry scientists deny the link to earthquakes, arguing that energy companies have been fracking for nearly sixty years. However it's only a dozen years ago that "slick-water fracks" were introduced. This form of fracking uses huge amounts of water mixed with sand and dozens of toxic chemicals like benzene, all of which is injected under extreme pressure to shatter the underground rock reservoir and release gas trapped in the rock pores. Not only does the practice utilize millions of gallons of freshwater per frack (taken from lakes, rivers, or municipal water supplies), the toxic chemicals mixed in the water to make it "slick" endanger groundwater aquifers and threaten to pollute nearby water-wells. Horizontal drilling and multi-stage fracking (which extend fractures across several kilometres) were introduced in 2004.

The Research Evidence
I think it's really hard to deny there's a connection when the frequency of Arkansas earthquakes dropped by two-thirds when the Arkansas Oil and Gas Commission banned fracking (see http://www.huffingtonpost.com/2011/04/21/fracking-shutdown-earthquakes-arkansas_n_851930.html). Note that they didn't stop entirely, which suggests that fault disruption may persist even after fracking stops.

Braxton County West Virginia also experienced a marked reduction in their quakes after the West Virginia Oil and Gas Commission forced fracking companies to cut back on the pressure and rate of salt water injection into the bedrock (see http://www.hurherald.com/cgi-bin/db_scripts/articles?Action=user_view&db=hurheral_articles&id=43334).

According to a joint study by Southern Methodist University and University of Texas-Austin, earthquakes started in the Dallas/Fort Worth region after a fracking disposal well there began operating in 2008 and stopped when it was closed in 2009 (see http://www.watershedsentinel.ca/content/does-gas-fracking-cause-earthquakes).