Some key takeaways...

Proved natural gas reserves in the Marcellus Shale gas play in Pennsylvania and West Virginia surpassed those in the Barnett Shale play of Texas to become the largest shale gas play in the United States.

Proved wet natural gas reserves decreased in four of the top five U.S. gas reserve states (Texas, Wyoming, Louisiana, and Oklahoma) in 2012 (Figure 3). Pennsylvania was the only state in the top five to report an increase (9.8 Tcf) in natural gas proved reserves in 2012, as a result of development of the Marcellus Shale play. In 2012, Pennsylvania went from fifth to the second largest gas reserve state.

U.S. oil and natural gas production both increased in 2012, reflecting the growing role of domestically produced hydrocarbons in meeting current and projected U.S. energy demand. U.S. production of crude oil and lease condensate increased about 16% from 2011 to 2012 (Figure 4).

Despite the drop in natural gas proved reserves in 2012, U.S. natural gas production increased about 6% from 2011 to 2012 (Figure 5).

You can view the entire report at http://www.eia.gov/naturalgas/crudeoilreserves/index.cfm