On June 10, 2013, the U.S. Energy Information Administration (EIA) released a report
assessing shale oil and gas resources in 137 shale formations in 41 countries outside of the United States. The report expanded upon EIA’s April 2011 assessment of 69 shale formations in 32 countries. In the updated report, EIA indicated that the current estimates of worldwide technically recoverable resources, including the United States, amount to 345 billion barrels of shale oil and 7,299 trillion cubic feet of shale gas. EIA estimates that shale resources account for 10 percent of global crude oil and 32 percent of the world’s natural gas. (The current estimate of global shale gas resources is 10 percent higher than EIA’s 2011 report, which did not include an assessment of shale oil.)
According to EIA, significant data gaps in global shale resources still exist. For example, potentially productive shale formations underlying large oil fields located in the Middle East and the Caspian region have not been assessed. EIA also indicated that although shale resources have revolutionized oil and gas production in the United States—representing 29 percent of total U.S. crude oil production and 40 percent of natural gas production in 2012—the economic recoverability of global shale resources and the market implications of abundant shale resources remain uncertain.