Introduction
This supplement to the U.S. Energy Information Administration's (EIA) U.S. Crude Oil and Natural Gas Proved Reserves, 2013 ranks the 100 largest U.S. oil and gas fields by their estimated 2013 proved reserves.
EIA defines a field as "an area consisting of a single reservoir or multiple reservoirs all grouped on, or related to, the same individual geological structural feature and/or stratigraphic condition. There may be two or more reservoirs in a field that are separated vertically by intervening impervious strata or laterally by local geologic barriers, or by both." This definition is not used by all states in their designation of fields; consequently, areas classified as individual fields by some states may be found combined in these tables or in the EIA Field Code Master List.
Particularly in the case of unconventional shale plays for both crude oil and natural gas, multiple areas or fields may have been combined into one entry within these ranking tables. The resultant field entry in the table is labeled as an area or unit, e.g., Marcellus Shale Area, Haynesville Shale Unit, Spraberry Trend Area, and Hugoton Gas Area.
The oil field production and reserves data include both crude oil and lease condensate. The gas field production and reserves data are total natural gas, wet after lease separation, which is the sum of associated-dissolved natural gas and nonassociated natural gas with natural gas plant liquids not yet removed.
The top 100's share of U.S. proved reserves in 2013
The top 100 oil fields as of December 31, 2013, accounted for 20.6 billion barrels of crude oil and lease condensate proved reserves, which was 56% of the U.S. total (36.5 billion barrels) in 2013 (Figure 1).
The top 100 gas fields as of December 31, 2013, accounted for 239.7 trillion cubic feet of total natural gas proved reserves, about 68% of the U.S. total natural gas proved reserves in 2013 (Figure 2).
Read entire supplement: Top 100 U.S. Oil and Gas Fields
