A Cabot Oil and Gas natural gas drill stands at a hydraulic fracturing site on Jan. 18, 2012 in South Montrose, Penn. The U.S. Geological Survey says a "remarkable" increase of earthquakes in the U.S. mid-continent since 2001 is "almost certainly" the result of oil and gas production. - 

Bob Moon: A highly-anticipated government study goes public today: A report by U.S. Geological Survey about possible links between natural gas drilling and unusual earthquake activity.

Elizabeth Wynne Johnson looks at the industry impact.

Elizabeth Wynne Johnson: Twelve years ago, seismologists noticed an uptick in the number of earthquakes rattling the Midwest. They wondered about a connection between the quakes and an increase in gas drilling. In particular, a then-emerging technique called hydraulic fracturing or “fracking.”

Andrew Coleman: There’s visions, I think, in laypeople’s heads of you fracture the rock 10,000 feet below the surface and you’ve got a cavity that runs up to the surface.

Industry analyst Andrew Coleman tracks drilling and production at Raymond James in Houston. He says it’s actually more like pencil-thin cracks that extract the natural gas from rock. This earthquake study, he says:

Coleman: I don’t think it changes the economics of natural gas extraction in the U.S.

But the report is bound to fuel attention and regulatory oversight from Washington.

The U.S. Geological Survey stops short of saying that fracking causes earthquakes. The study does find the earthquakes are clustered around underground wells used to store the wastewater.

I’m Elizabeth Wynne Johnson for Marketplace.