A new drilling technique has been developed that will enable oil & gas companies to tap into significant quantities of oil previously out-of-reach in the United States. Billions of dollars are being invested to access oil deposits in North Dakota, Colorado, Texas and California. Oil executives and analysts believe that by 2015, the new fields could produce as much as 2 million barrels of oil a day, more than the entire Gulf of Mexico currently produces. It is expected that this new drilling will raise U.S. production by 10%, and by at least 20% over the next five years. Within 10 years oil imports could be reduced by more than half. The drilling process is much like the hydraulic fracturing technique used to extract natural gas from shale rock formations. The natural gas process involves drilling down and horizontally into rock, and pumping water, sand and chemicals into the hole to crack the shale, allowing the gas to flow up. As oil molecules are sticky and bigger than gas molecules, drillers came up with a method to increase the number of cracks in the rock and use different chemicals to free up oil at a low cost.