Ray Gerrish repairs a drilling rig near Watford City, N.D. Oil industry analysts predict that oil prices will have to remain low for at least several months before having a significant effect on U.S. production. Jim Gehrz/MCT/Landov hide caption

itoggle caption Jim Gehrz/MCT/Landov

Pumpjacks at the Inglewood oil fields in California in March. Some of the most controversial methods of oil extraction, like fracking, oil sands production and Arctic drilling, are also expensive. That's made them less profitable as the price of oil continues to fall. Richard Vogel/AP hide caption

itoggle caption Richard Vogel/AP

Guillermo Gomez, husband of Vilma Marenco, holds his daughter in their home in Northeast Houston. Marenco was killed in April after being hit by an uninsured trucker who ran a red light. Mayra Beltran/Houston Chronicle hide caption

itoggle caption Mayra Beltran/Houston Chronicle

When Dawn Gioia first received a request to lease mineral rights under her home, in a downtown neighborhood in Brighton, Colo., she thought it was a scam. Lesley McClurg/Colorado Public Radio hide caption

itoggle caption Lesley McClurg/Colorado Public Radio

At the Pittsburgh International Airport, Consol Energy will begin extracting gas — even under the runways. MeRyan/Wikimedia Commons hide caption

itoggle caption MeRyan/Wikimedia Commons

A worker stands on top of a storage bin on July 27, 2011, at a drilling operation in Claysville, Pa. The dust is from powder mixed with water for hydraulic fracturing. Keith Srakocic/AP hide caption

itoggle caption Keith Srakocic/AP