U.S. Crude Oil, Natural Gas, and 

Natural Gas Liquids Proved 

Reserves, 2010

August 2012

Independent Statistics & Analysis

www.eia.gov

U.S. Department of Energy

Washington, DC 20585
U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 i

This report was prepared by the U.S. Energy Information Administration (EIA), the statistical and 

analytical agency within the U.S. Department of Energy. By law, EIA’s data, analyses, and forecasts are 

independent of approval by any other officer or employee of the United States Government. The views 

in this report therefore should not be construed as representing those of the Department of Energy or 

other Federal agencies.
U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 ii

Table of Contents

Summary .......................................................................................................................................................1

Background ...................................................................................................................................................3

Oil proved reserves (crude oil plus lease condensate)............................................................................4

Overview ...........................................................................................................................................4

Wet natural gas proved reserves (includes natural gas plant liquids) ....................................................8

Overview ...........................................................................................................................................8

Dry natural gas reserves........................................................................................................................13

Natural gas liquids proved reserves ......................................................................................................13

Lease Condensate ...........................................................................................................................13

Natural Gas Plant Liquids................................................................................................................14

List of additional data tables and maps.................................................................................................14
U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 iii

Tables

Table 1. Changes to proved reserves, 2010..................................................................................................1

Table 2. Changes to proved reserves of wet natural gas by source, 2010 ...................................................8

Table 3. Principal shale gas plays: natural gas production and proved reserves, 2008-2010 ....................11

Table 4. Total U.S. proved reserves of wet natural gas, and crude oil plus lease condensate, 2001-2010

....................................................................................................................................................................19

Table 5. Total Natural gas proved reserves, reserves changes, and production, wet after lease 

separation, 2010 .........................................................................................................................................20

Table 6. Crude oil plus lease condensate proved reserves, reserves changes, and production 2010 .......21

Table 7. Total U.S. proved reserves of crude oil, natural gas, and lease condensate, 2001-2010 .............22

Table 8. Crude oil proved reserves, reserves changes, and production, 2010...........................................23

Table 9. Dry natural gas proved reserves, reserves changes, and production, 2010.................................24

Table 10. Lease condensate proved reserves, reserves changes, and production, 2010...........................25

Table 11. Nonassociated natural gas proved reserves, reserves changes, and production, wet after lease 

separation, 2010 .........................................................................................................................................26

Table 12. Associated-dissolved natural gas proved reserves, reserves changes, and production, wet after 

lease separation, 2010................................................................................................................................27

Table 13. Shale natural gas proved reserves and production, 2007 – 2010...............................................28

Table 14. Shale natural gas proved reserves, reserves changes, and production, wet after lease 

separation, 2010 .........................................................................................................................................29

Table 15. Coalbed methane proved reserves and production, 2006 – 2010 .............................................30

Table 16. Coalbed methane proved reserves, reserves changes, and production, 2010...........................31

Table 17. Natural gas plant liquids proved reserves and production, 2009 – 2010 (excludes lease 

condensate) ................................................................................................................................................32

Table 18. Reported proved nonproducing reserves of crude oil, lease condensate, nonassociated gas, 

associated dissolved gas, and total gas (wet after lease separation) 2010a

...............................................33
U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 iv

Figures

Figure 1. U.S. oil and natural gas proved reserves........................................................................................2

Figure 2. U.S. crude oil plus lease condensate proved reserves, 1980-2010 ...............................................5

Figure 3. U.S. weekly oil rig count and average spot price of West Texas Intermediate crude oil ..............6

Figure 4. Oil proved reserves changes in 2010 .............................................................................................6

Figure 5. U.S. wet natural gas proved reserves, 1980-2010 .........................................................................8

Figure 6. Annual change in u.s. natural gas proved reserves, shale and other sources, 2007-2010............9

Figure 7. Shale gas proved reserves by State..............................................................................................10

Figure 8. Natural gas proved reserves changes in 2010 .............................................................................12

Figure 9. Oil proved reserves by state/area, 2010......................................................................................15

Figure 10. Changes in oil proved reserves by state/area, 2009 to 2010 ....................................................16

Figure 11. Wet natural gas proved reserves by state/area, 2010 ..............................................................17

Figure 12. Changes in wet natural gas proved reserves by state/area, 2009 to 2010 ...............................18
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 1

Summary

Proved reserves of U.S. oil and natural gas in 2010 rose by the highest amounts ever recorded since the 

U.S. Energy Information Administration (EIA) began publishing proved reserves estimates in 1977. 

• Net additions to proved reserves of crude oil plus lease condensate in 2010 totaled 2.9 billion 

barrels, surpassing the previous high of 1.8 billion barrels added in 2009 by 63 percent (Table 1). 

• Net additions of wet natural gas in 2010 totaled 33.8 trillion cubic feet (Tcf), nearly 5 Tcf (17 

percent) higher than the previous record of 28.8 Tcf, also added in 2009.

Table 1. Changes to proved reserves, 2010

Crude oil plus lease condensate Wet natural gas

billion barrels trillion cubic feet

Reserves at December 31, 2009 22.3 283.9

 Total discoveries 2.1 48.9

 Net revisions 1.9 4.1

 Net adjustments, sales, acquisitions 0.9 4.1

 Production -2.0 -23.2

Net change in proved reserves 2.9 33.8

Reserves at December 31, 2010 25.2 317.6

Percentage change in proved reserves 12.8% 11.9%

Notes: Wet natural gas includes natural gas plant liquids.

Percent change calculated from unrounded numbers.

Source: U.S. Energy Information Administration, Form EIA-23

An important factor for each fuel was the expanding application of horizontal drilling and hydraulic 

fracturing in shale and other “tight” (very low permeability) formations, the same technologies that 

spurred substantial gains in natural gas proved reserves in recent years. Helping to drive proved 

reserves increases in 2010 were also higher prices used to assess economic viability relative to the prices 

used for the 2009 reporting year, particularly for oil. 

While proved reserves of natural gas began increasing moderately in the late 1990s, it was not until the 

mid-2000s that volumes grew dramatically, in step with intensifying horizontal drilling programs (Figure

1). More recently, tight oil developments have contributed to the reversal of more than two decades of 

generally declining U.S. proved oil reserves. For both oil and natural gas, these increases in proved 

reserves represent a growing role for domestically-produced hydrocarbons in meeting current and 

projected U.S. energy demands.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 2

Figure 1. U.S. oil and natural gas proved reserves

Proved reserves of crude oil and lease condensate rose 13 percent to 25.2 billion barrels in 2010, 

marking the largest annual increase since 1977 and the highest total level since 1991. Proved reserves 

increased in each of the five largest crude oil and lease condensate areas (Texas, the Gulf of Mexico 

Federal Offshore, Alaska, California, and North Dakota) between 2009 and 2010. Of these, Texas had 

the largest increase, 860 million barrels (16 percent), resulting mostly from ongoing development in the 

Permian and Western Gulf Basins in the western and south-central portions of the state. North Dakota 

reported the second largest increase, 829 million barrels (78 percent), driven by development activity in 

the Williston Basin. Collectively, North Dakota and Texas accounted for nearly 60 percent of the net 

increase in total U.S. proved reserves in 2010.

Natural gas proved reserves1

This report summarizes changes to U.S. oil and natural gas proved reserves during 2010. As of this 

release date (August 2, 2012), EIA is currently collecting data for the 2011 reporting year, and 

anticipates releasing a summary of 2011 developments in the first quarter of 2013.

 (estimated as “wet” natural gas, including natural gas plant liquids) 

increased by 12 percent in 2010 to 317.6 Tcf, the twelfth consecutive annual increase and the first year 

U.S. volumes surpassed 300 Tcf. Four of the five largest natural gas states (Texas, Louisiana, Oklahoma, 

and Colorado) registered net gains, with Louisiana and Texas adding a combined 17.8 Tcf, over one-half 

of the overall national increase. Pennsylvania’s proved natural gas reserves more than doubled in 2010, 

contributing about one-fifth of the overall U.S. increase. Expanding shale gas developments in these and 

other areas, perhaps most notably in Pennsylvania’s portion of the Appalachian Basin in the Marcellus 

play, drove overall increases in 2009 and 2010. 

 1 Natural gas, wet after lease separation, is the volume of natural gas remaining after removal of lease condensate in lease 

and/or field separation facilities, if any, and after exclusion of nonhydrocarbon gases where they occur in sufficient quantity to 

render the gas unmarketable. Natural gas plant liquids may be recovered from volumes of natural gas, wet after lease 

separation, at natural gas processing plants.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 3

Background

EIA provides annual estimates of U.S. proved reserves of crude oil, natural gas, and natural gas liquids 

(NGLs) based on filed responses to Form EIA-23, Annual Survey of Domestic Oil and Gas Reserves, an 

annual survey of about 1,200 domestic operators. 

Proved reserves are those volumes of oil and natural gas that geologic and engineering data 

demonstrate with reasonable certainty to be recoverable in future years from known reservoirs under 

existing economic and operating conditions. Reserves estimates change from year to year as new 

discoveries are made, existing fields are more thoroughly appraised, existing reserves are produced, and 

as prices and technologies change. Discoveries include new fields, identification of new reservoirs in 

previously discovered fields, and extensions, which are reserve additions that result from additional 

drilling and exploration in previously discovered reservoirs. Within a given year, extensions typically 

account for a large percentage of total discoveries. While discoveries of new fields and reservoirs are 

important indicators of new resources, they generally comprise a small percentage of overall reserve 

additions on an annual basis. Revisions occur primarily when operators change their estimates of what 

they will be able to produce from the properties they operate using existing technology and prices.

Several factors influence reserves estimates, but crude oil and natural gas prices are particularly 

important. Higher prices typically increase estimates (positive revisions) as operators consider a broader 

portion of the resource base economically producible, or proved. Lower prices generally reduce 

estimates (negative revisions) as the economically producible base contracts.

Both EIA and the Securities and Exchange Commission (SEC) require oil and gas companies to provide 

information on their oil and gas reserves. The 2010 reporting period represents the second year 

companies reporting to the SEC followed updated rules for determining the prices underpinning their 

proved reserves estimates. The revised rules, which were designed to make estimates less sensitive to 

price fluctuations during the year, require companies to use an average of the 12 first-day-of-the-month 

prices. Prior to the 2009 reporting year, companies’ estimates were based on the market price on the 

last trading day of the year. The 12 first-day-of-the-month average crude oil and natural gas spot prices2

There are also important differences between these two reporting systems. First, EIA collects 

information from both publicly traded and privately held companies, while SEC reporting requirements 

apply only to companies with more than $10 million in assets and whose securities are held by more 

than 500 owners. Second, companies reporting to EIA (both public and private) include gross operated 

 

for 2010 were $79.79 per barrel and $4.39 per million Btu (MMbtu), representing increases of 31 

percent and 15 percent, respectively, from the previous year. Spot market prices are not necessarily the 

prices used by operators in their reserves estimates, because actual prices received by operators 

depend on their contractual arrangements, location, quality, etc. They do provide a benchmark or trend 

indicator.

 2 Spot prices used were the Cushing, OK West Texas Intermediate for crude oil and the Henry Hub Gulf Coast for natural gas.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 4

reserves (irrespective of their ownership share), while the companies reporting to the SEC include only 

their “owned” reserves (irrespective of operator). 3

It is important to note that the average natural gas price used in estimating proved reserves for 2010

does not reflect the more recent and prolonged downward trend in natural gas prices. For the 2011 

reporting period, the average natural gas price fell more than 5 percent to $4.15 per MMBtu, reflecting 

the dual impact of continued increases in domestic production (due largely to shale gas development) 

and significantly rising inventories. This held particularly true during the second half of 2011, when the 

daily Henry Hub spot price dipped below $4.00 per MMBtu, averaging $3.17 per MMBtu in December 

and finishing the year at $2.98 per MMBtu. It can be expected, therefore, that price-driven negative 

revisions will affect overall natural gas proved reserves additions in 2011.

 

Conversely, the 12 first-day-of-the-month average spot price of Cushing, Oklahoma WTI crude oil rose 

from $79.79 per barrel in 2010 to $95.84 per barrel in 2011. EIA therefore anticipates price-driven 

positive revisions will add to proved reserves of crude oil in 2011. 

The aggregated production data for crude oil, natural gas, and NGLs includes volumes that have been 

reported to EIA by operators on Form EIA-23, and, for non-reported production, volumes that are based 

on EIA estimates. These production numbers are offered only as an indicator of production trends and 

may differ from EIA’s official production series based on State-reported data and provided elsewhere on 

the EIA website for oil and natural gas

Oil proved reserves (crude oil plus lease condensate)

Overview

The 2009 Reserves Report detailed the major increases in the country’s natural gas proved reserves 

attributable to expanding exploration and development programs in shale formations such as the 

Barnett in Texas and the Haynesville in Louisiana. Central to the increases was the combination of 

horizontal drilling and hydraulic fracturing technologies. While that Report acknowledged the increase 

in 2009 oil proved reserves were also facilitated by the dual application of these technologies in shale 

and other tight formations, gains were especially pronounced in 2010, taking place primarily onshore in 

the lower 48 states (Figure 2).

 3 Additional information concerning EIA and SEC reserves can be found in a supplemental report to the 2009 reserves summary.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 5

Figure 2. U.S. crude oil plus lease condensate proved reserves, 1980-2010

Overall reported U.S. oil proved reserves rose by nearly 3.0 billion barrels in 2010, driven essentially 

equally by net revisions and a fourth consecutive increase in total discoveries, which added a combined 

4.0 billion barrels (more than double the year’s production) (Figure 4). Among individual states, the 860 

million barrel addition in Texas represented the year’s largest volumetric increase in oil proved reserves, 

due in large part to expanding horizontal drilling and hydraulic fracturing programs in the Eagle Ford and 

other shale formations. Similar programs were essential in adding significantly to proved oil reserves in 

other states, particularly North Dakota, where drilling in the Bakken and underlying Three Forks 

formations in the Williston Basin accounted for the bulk of North Dakota’s 829 million barrel net 

addition in 2010.

Weekly active rotary rig counts can be a useful gauge of exploration and development activity generally, 

with changes in the horizontal count, in particular, indicating the pace of activity in shale formations and 

other tight plays. During 2010, the overall number of active oil-directed drilling rigs in the United States 

rose by 79 percent, an increase driven largely by a near tripling of horizontal rigs usage. Horizontal rigs 

accounted for 27 percent of active oil rigs at the beginning of 2010; that share had climbed to 44 

percent by year’s end (Figure 3). 
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 6

Figure 3. U.S. weekly oil rig count and average spot price of West Texas Intermediate crude oil

Figure 4. Oil proved reserves changes in 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 7

Total Discoveries. Total discoveries consist of discoveries of new fields, identification of new reservoirs 

in fields discovered in prior years, and extensions (reserve additions that result from the additional 

drilling and exploration in previously discovered reservoirs). Total discoveries added 2,059 million 

barrels to U.S. oil reserves in 2010, the highest volume of total discoveries since 2001. As is typical, 

extensions comprise the bulk of total discoveries (86 percent) (Figure 4). 

Geographically, the bulk of total oil discoveries in 2010 came from Texas, North Dakota, and the 

deepwater Gulf of Mexico. Texas led in 2010, with discoveries of 752 million barrels. North Dakota 

marked its second consecutive year as a major source of total discoveries, adding 565 million barrels. As 

in 2009, North Dakota’s discoveries (mostly extensions) are associated with rapid growth in reserves of 

the Bakken and underlying Three Forks formations. Total discoveries in the Gulf of Mexico Federal 

Offshore added 232 million barrels in 2010, a decline of 29 percent from the 328 million barrels of 

discoveries in 2009, reflecting the impact of the moratorium on most deepwater Gulf of Mexico drilling 

activity following the Macondo well explosion in April 2010.

Net Revisions and Other Changes. Revisions to proved reserves occur primarily when operators change 

their estimates of what they will be able to produce from the properties they operate using existing 

technology and prices. These revisions reflect changing prices, changing cost structures (for example, 

because of technological advances), and other factors. Other small changes occur when operators buy 

and sell properties (revaluing the proved reserves in the process), and as various adjustments are made 

to reconcile estimated volumes.

Net revisions added 1.9 billion barrels to oil proved reserves in 2010, the highest level since 1999 and 

largely reflective of the significant increase in oil prices relative to 2009. Under the SEC rules adopted 

for the 2009 reporting year, the 12 first-day-of-the-month average spot price for West Texas 

Intermediate (WTI) crude oil in 2010 was $79.79 per barrel, an increase of 31 percent over the 12 firstday-of-the-month average price in 2009 ($61.08).

The net change to U.S. proved oil reserves associated with buying and selling properties and 

adjustments was modest compared with net revisions in 2010. The net of sales and acquisitions added 

667 million barrels to the U.S. totals, significantly more than the prior year (95 million barrels in 2009), 

but much less than net revisions of 1,943 million barrels in 2010. Adjustments (reserves changes that 

EIA cannot attribute to any other category) added 188 million barrels in 2010.

Production. Operators reported oil production of about 2.0 billion barrels in 2010, an increase of 3 

percent from 2009. This represents the country’s second consecutive annual increase and its highest 

level since 2004. Production from the onshore lower 48 states (primarily Texas and North Dakota), 

which was up nearly 8 percent from the previous year, more than offset declines in Alaska and the Gulf 

of Mexico Federal Offshore. While production from Alaska has generally declined for several years, the 

dip in Gulf of Mexico Federal Offshore output followed a major deepwater-driven production increase in 

2009 (again reflecting the influence of the drilling moratorium).
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 8

Wet natural gas proved reserves (includes natural gas plant liquids)

Overview

Total reported U.S. proved reserves of wet natural gas rose by 33.8 Tcf in 2010, supplanting the 2009 

reporting year’s 28.8 Tcf as the highest annual volumetric increase on record and boosting the country’s 

proved reserves to over 300 Tcf for the first time (Figure 5). The increase was driven largely by an eighth 

consecutive annual rise in discoveries, which added nearly 50 Tcf (mostly from extensions) (Table 2). 

U.S. natural gas proved reserves have increased in every year since 1999, with the pace accelerating in 

recent years in step with expanding exploration and development activity in several of the nation’s shale 

formations.

Figure 5. U.S. wet natural gas proved reserves, 1980-2010

Table 2. Changes to proved reserves of wet natural gas by source, 2010

trillion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Proved Revisions & Proved

Reserves Discoveries Other Changes Production Reserves

Source of Gas Year-End 2009 2010 2010 2010 Year-End 2010

Coalbed Methane 18.6 0.5 0.3 -1.9 17.5

Shale 60.6 30.8 11.4 -5.3 97.4

Other (Conventional & Tight)

 Lower 48 Onshore 182.6 16.9 -4.4 -13.5 181.7

 Lower 48 Offshore 12.9 0.6 0.8 -2.2 12.1

 Alaska 9.2 0.0 0.0 -0.3 8.9

TOTAL 283.9 48.9 8.1 -23.2 317.6

Source: U.S. Energy Information Administration, Form EIA-23
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 9

The combination of horizontal drilling and hydraulic fracturing in shale formations continues to be 

instrumental to the expansion of U.S. natural gas proved reserves over the last few years. This held 

especially true in 2010, when an increase in shale natural gas reserves of 36.8 Tcf offset a decrease in 

net reserves from all other sources combined (Figure 6). The significant impact of shale developments 

can also be seen by examining the share of shale gas relative to total U.S. natural gas proved reserves. 

That share has increased steadily and significantly, from less than 10 percent in 2007 to over 30 percent 

in 2010 (Figure 6).

Figure 6. Annual change in U.S. natural gas proved reserves, shale and other sources, 2007-2010

At the state level, Texas’ 9.3 Tcf addition represents the largest volumetric increase in natural gas 

proved reserves in 2010, driven by continued development of the Barnett and Haynesville/Bossier shale 

formations. In Louisiana, an increase in total proved natural gas reserves of 8.5 Tcf was largely the result 

of ongoing drilling programs at the Haynesville shale formation. Shale activity contributed 10.8 Tcf to 

Louisiana’s proved natural gas reserves, offsetting declines from non-shale sources. In Pennsylvania, 

expanding drilling programs at the Marcellus shale formation drove the state’s 7.1 Tcf increase in total 

proved natural gas reserves, more than doubling year-end 2009 volumes. Figure 7 shows the shale gas 

proved reserves in the nation’s key shale states in 2010, which also included Arkansas (the Fayetteville

shale play) and Oklahoma (the Woodford shale play).
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 10

Figure 7. Shale gas proved reserves by State

Nearly all (96 percent) of the country’s shale natural gas proved reserves in 2010 came from the six 

largest shale plays (Table 3). While the Barnett again ranked as the largest shale gas play in the United 

States, significantly higher increases over 2009 proved reserves were registered by the 

Haynesville/Bossier (which more than doubled 2009 volumes) and the Marcellus (which nearly tripled). 

Among these six shale plays, the only decline from 2009 volumes was in the Antrim of northern 

Michigan—a mature, shallow biogenic shale gas play discovered in 1986 that is no longer being 

developed at the same pace as the other leading shales. EIA has a series of maps showcasing the 

nation’s shale gas resources for both shale plays and geologic basins.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 11

Table 3. Principal shale gas plays: natural gas production and proved reserves, 2008-2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Shale Play Production Reserves Production Reserves Production Reserves Production Reserves

Barnett 1,501 22,492 1,745 26,493 1,918 31,040 173 4,547

Haynesville/Bossier 25 1,031 321 10,468 1,451 24,451 1,130 13,983

Fayetteville 279 3,833 527 9,070 794 12,526 267 3,456

Woodford 168 3,845 249 6,389 403 9,670 154 3,281

Marcellus 2 102 76 4,478 476 13,199 400 8,721

Antrim 122 2,894 132 2,499 120 2,306 -12 -193

Sub-total 2,097 34,197 3,050 59,397 5,162 93,192 2,112 33,795

Other Shale Plays 19 231 60 1,247 174 4,257 114 3,010

All U.S. Shale Plays 2,116 34,428 3,110 60,644 5,336 97,449 2,226 36,805

Note: The above table is based on shale gas proved reserves and production volumes reported and imputed from data on Form EIA-23.

For certain reasons (e.g., incorrect or incomplete submissions, misidentification of shale versus non-shale reservoirs) 

the actual proved reserves and production of natural gas from shale plays may be higher or lower. 

The production estimates are offered only as an observed indicator of production trends and may differ 

from EIA production volumes listed elsewhere on the EIA web site.

Sources: U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, 2008 through 2010 annual reports.

 2008 2009 2010 Change 2010-2009

The sustained lower price environment for natural gas relative to oil has encouraged operators to shift 

drilling and development programs toward “liquids-rich” areas within these and other shale gas plays 

that offer a higher yield of natural gas liquids (NGLs) and crude oil. These areas include southwestern

portions of the Marcellus in Pennsylvania and parts of the Eagle Ford Shale covering much of south

Texas. Due to their relative price premium over natural gas, the production of crude oil and NGLs along 

with natural gas improves project economics.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 12

Figure 8. Natural gas proved reserves changes in 2010

Total Discoveries. Total wet natural gas discoveries of 48.9 Tcf represented the eighth consecutive 

annual increase and were the highest volume of discoveries since EIA began publishing proved reserves 

estimates in 1977 (Figure 8). In 2010, 95 percent of total wet natural gas discoveries (and a similar share 

of shale gas discoveries) came from extensions of existing fields. New field discoveries and new 

reservoir discoveries in previously discovered fields totaled 0.9 Tcf and 1.7 Tcf, respectively, each 

representing a decrease from 2009. Texas and Louisiana, with discoveries of 13.0 Tcf and 11.4 Tcf, 

respectively, were the leading individual states, while Pennsylvania more than doubled its total 

discoveries, adding 6.8 Tcf. In each of these states, shale gas developments drove volumetric additions. 

Pennsylvania, in particular, may expect substantial proved reserves increases for the 2011 reporting 

year, given the significant quickening pace of drilling and development programs in the Marcellus.

Net Revisions and Other Changes. For 2010, net revisions of wet natural gas proved reserves added 4.1 

Tcf. Positive revisions of 42.4 Tcf were the largest since 1999, reflecting an increase in the price used to 

estimate reserves and, consequently, an enhanced ability to economically produce natural gas, 

particularly from relatively costly unconventional sources such as shale. The 12 first-day-of-the-month 

average spot price at Henry Hub rose from $3.83 per MMBtu in 2009 to $4.39 per MMBtu in 2010.

The net change to wet natural gas proved reserves from the purchase and sale of properties and 

adjustments (4.1 Tcf) was comparable to net revisions; both were significantly less than 2010 

extensions.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 13

Production. As reported on the EIA Form-23 survey, production of wet natural gas in 2010 totaled 23.2

Tcf, up 3 percent from 2009, marking the fifth consecutive increase and the highest since EIA began 

reporting. Three states – Louisiana, Texas, and Pennsylvania – accounted for nearly three-quarters of 

the overall increase, much of which was tied to expanded drilling programs in shale formations.

Dry natural gas reserves

Dry natural gas is that volume of gas that remains after all of the liquefiable hydrocarbons and 

nonhydrocarbon impurities are removed from the natural gas stream; first at lease separation facilities 

near the producing well(lease condensate), then downstream at a natural gas processing plant (natural 

gas plant liquids). Proved reserves of U.S. dry natural gas also increased by 12 percent from 2009 to 

2010, to 304.6 Tcf.4

Natural gas liquids proved reserves

Natural gas liquids are those hydrocarbons in natural gas that are separated from the gas as liquids 

through the process of absorption, condensation, adsorption, cooling in gas separators, gas processing, 

or gas cycling plants. Generally, natural gas liquids include lease condensate and natural gas plant 

liquids.

EIA continues to provide separate estimates of lease condensate and natural gas plant liquids volumes, 

and changes to proved reserves of each during 2010 are summarized in this section.

Because NGLs sell at a premium to natural gas, there is often an economic incentive for operators to 

focus exploration and development activities on areas that have natural gas with high liquids content. 

This "liquids boost" is especially important in the development of unconventional resources (such as 

shale gas) because of the relatively high cost of drilling and completing horizontal wells. The high liquids 

content of certain shale formations helps operators to profitably develop shale gas resources during 

periods of low natural gas prices. 

Lease Condensate

U.S. lease condensate proved reserves increased from 1,633 million barrels in 2009 to 1,914 million 

barrels in 2010, a 17 percent increase driven primarily by extensions. By a considerable margin, Texas 

had the largest increase in lease condensate proved reserves in 2010 (192 million barrels), followed by 

North Dakota and Oklahoma. In these (and other) states, additions to lease condensate proved reserves 

can be closely linked to expanding drilling programs in liquids-rich portions of shale and other tight 

formations, such as the Eagle Ford in Texas and the Bakken in North Dakota. Lease condensate 

comprised almost eight percent of total oil proved reserves in 2010.

 4 Detail on dry natural gas proved reserves is available in the additional data tables, “Table 9. Dry Natural Gas Proved Reserves, 

Reserves Changes, and Production, 2010.”
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 14

U.S. lease condensate production increased 26 percent, from 178 million barrels in 2009 to 224 million 

barrels in 2010, the highest production volume registered since EIA began publishing proved reserves 

estimates.

Lease condensate, which is extracted from the natural gas production stream at the field (lease) level, is 

often blended into other crude oil to enhance the blend quality for refiners.

Natural Gas Plant Liquids

U.S. natural gas plant liquids proved reserves rose from 8,557 million barrels in 2009 to 9,809 million 

barrels in 2010, an increase of 15 percent. Texas had the largest volumetric increase in natural gas plant 

liquids proved reserves in 2010, followed by Oklahoma and Colorado. As is the case with lease 

condensate, increasing proved reserves of natural gas plant liquids is associated with escalating drilling 

activity in shale formations, including the Barnett in Texas and Woodford in Oklahoma.

U.S. natural gas plant liquids production in 2010 increased more than 4 percent, from 714 million barrels 

in 2009 to 745 million barrels in 2010.

Natural gas plant liquids remain in gaseous form at the surface and must be separated at a gas 

processing plant. Once extracted, these liquids are separated into distinct products, or "fractions," such 

as propane, butane, and ethane.

Additional data tables and maps

For more detailed 2010 proved reserves information than discussed in the report see Tables 4-18 and 

Figures 9-12.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 15

Figure 9 shows a thematic map of the 2010 crude oil proved reserves volumes by State and Federal 

Offshore areas, and Figure 10 shows the change in crude oil proved reserves by area from 2009 to 2010.

Figure 9. Oil proved reserves by state/area, 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 16

Figure 10. Changes in oil proved reserves by state/area, 2009 to 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 17

Similarly, Figure 11 shows a thematic map of the 2010 wet natural gas proved reserves volumes by State 

and Federal Offshore areas, and Figure 12 shows the change in wet natural gas proved reserves by area 

from 2009 to 2010.

Figure 11. Wet natural gas proved reserves by state/area, 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 18

Figure 12. Changes in wet natural gas proved reserves by state/area, 2009 to 2010

Some areas on the maps are shaded but display no volume information to avoid disclosure of individual 

company data.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 19

Table 4. Total U.S. proved reserves of wet natural gas, and crude oil plus lease condensate, 2001-2010

Revisionsa Net of Salesb New Reservoir Provedd Change

Net and and New Field Discoveries Totalc Estimated Reserves from

Adjustments Revisions Adjustments Acquisitions Extensions Discoveries in Old Fields Discoveries Production 12/31 Prior Year

Year (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11)

Wet Natural Gas (billion cubic feet, 14.73 psia, 60 degrees Fahrenheit)

2001 1,849 -2,438 -589 2,715 17,183 3,668 2,898 23,749 20,642 191,743 5,233

2002 4,006 1,038 5,044 428 15,468 1,374 1,752 18,594 20,248 195,561 3,818

2003 2,323 -1,715 608 1,107 17,195 1,252 1,653 20,100 20,231 197,145 1,584

2004 170 825 995 1,975 19,068 790 1,244 21,102 20,017 201,200 4,055

2005 1,693 2,715 4,408 2,674 22,069 973 1,243 24,285 19,259 213,308 12,108

2006 946 -2,099 -1,153 3,178 22,834 425 1,197 24,456 19,373 220,416 7,108

2007 990 15,936 16,926 452 28,255 814 1,244 30,313 20,318 247,789 27,373

2008 271 -3,254 -2,983 937 27,800 1,229 1,678 30,707 21,415 255,035 7,246

2009 5,923 -1,899 4,024 -222 43,500 1,423 2,656 47,579 22,537 283,879 28,844

2010 1,292 4,055 5,347 2,766 46,283 895 1,701 48,879 23,224 317,647 33,768

Crude Oil plus Lease Condensate (million barrels of 42 U.S. gallons)

2001 -61 -346 -407 -53 1,002 1,480 358 2,840 2,133 23,843 326

2002 423 682 1,105 51 600 318 187 1,105 2,082 24,023 180

2003 192 -9 183 -416 530 717 137 1,384 2,068 23,106 -917

2004 80 444 524 37 731 36 159 926 2,001 22,592 -514

2005 237 558 795 327 946 209 57 1,212 1,907 23,019 427

2006 109 43 152 189 685 38 62 785 1,834 22,311 -708

2007 21 1,275 1,296 44 865 81 87 1,033 1,872 22,812 501

2008 318 -2,189 -1,871 187 968 166 137 1,271 1,845 20,554 -2,258

2009 46 2,008 2,054 95 1,305 141 95 1,541 1,929 22,315 1,761

2010 188 1,943 2,131 667 1,766 124 169 2,059 1,991 25,181 2,866

a

 Revisions and adjustments = Col. 1 + Col. 2. 

b Net of sales and acquisitions = acquisitions - sales

c Total discoveries = Col. 5 + Col. 6 + Col. 7. 

d

 Proved reserves = Col. 10 from prior year + Col. 3 + Col. 4 + Col. 8 - Col. 9. 

NA = Not available

Notes: Old means discovered in a prior year. New means discovered during the report year. 

The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves" and Form EIA-64A,

"Annual Report of the Origin of Natural Gas Liquids Production." They may differ from the official EIA production data for crude oil, lease condensate, and wet natural gas 

for 2010 contained in the Petroleum Supply Annual 2010, DOE/EIA-0340(10) and the Natural Gas Annual 2010, DOE/EIA-0131(10). 

EIA Petroleum & Other Liquids Data EIA Natural Gas Data

Sources: U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, 2001 through 2010 annual reports.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 20

Table 5. Total Natural gas proved reserves, reserves changes, and production, wet after lease 

separation, 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 9,183 -3 628 455 132 0 15 0 0 319 8,917

Lower 48 States 274,696 1,295 41,766 37,884 10,450 13,348 46,268 895 1,701 22,905 308,730

Alabama 2,948 60 214 180 272 153 29 3 0 231 2,724

Arkansas 10,872 -34 1,072 301 393 807 3,083 0 27 952 14,181

California 2,926 4 575 476 3 0 13 1 0 255 2,785

 Coastal Region Onshore 169 2 39 17 1 0 0 0 0 12 180

 Los Angeles Basin Onshore 91 3 9 5 0 0 0 0 0 6 92

 San Joaquin Basin Onshore 2,609 -1 514 451 2 0 9 1 0 232 2,447

 State Offshore 57 0 13 3 0 0 4 0 0 5 66

Colorado 24,081 646 3,127 3,834 255 241 2,986 23 29 1,672 25,372

Florida 7 64 0 0 0 0 0 0 0 15 56

Kansas 3,500 166 736 178 18 24 29 4 1 327 3,937

Kentucky 2,919 -15 110 576 0 42 408 0 0 103 2,785

Louisiana 20,970 -693 3,183 3,222 746 861 11,045 49 285 2,215 29,517

 North 17,273 -451 2,604 2,495 604 564 10,751 48 174 1,728 26,136

 South Onshore 2,969 -5 510 640 72 253 292 1 97 410 2,995

 State Offshore 728 -237 69 87 70 44 2 0 14 77 386

Michigan 2,805 258 265 385 539 725 1 2 0 157 2,975

Mississippi 922 3 77 71 31 13 33 0 0 88 858

Montana 993 -22 105 101 41 30 88 0 1 94 959

New Mexico 16,644 -32 2,364 1,960 161 469 514 0 3 1,312 16,529

 East 4,558 -159 537 466 148 469 364 0 3 438 4,720

 West 12,086 127 1,827 1,494 13 0 150 0 0 874 11,809

New York 196 104 35 83 2 11 0 56 0 36 281

North Dakota 1,213 -5 950 810 53 152 496 28 3 105 1,869

Ohio 896 127 68 59 374 239 8 0 0 73 832

Oklahoma 24,207 -271 3,448 3,716 234 1,625 4,890 54 1 1,822 28,182

Pennsylvania 7,018 -357 2,914 1,953 683 938 5,824 51 911 595 14,068

Texas 85,034 1,263 11,639 9,893 2,807 3,442 12,317 552 129 7,389 94,287

 RRC District 1 1,523 -110 459 347 505 451 1,108 126 16 122 2,599

 RRC District 2 Onshore 1,909 5 356 323 19 32 190 328 10 253 2,235

 RRC District 3 Onshore 2,802 90 517 342 197 213 188 21 27 545 2,774

 RRC District 4 Onshore 7,057 37 1,143 895 220 190 993 25 3 941 7,392

 RRC District 5 22,623 53 1,598 1,292 1 5 3,504 0 0 1,796 24,694

 RRC District 6 13,257 413 2,755 2,776 523 989 2,250 52 52 1,053 15,416

 RRC District 7B 2,424 87 304 270 3 0 258 0 0 175 2,625

 RRC District 7C 5,430 125 608 806 653 511 563 0 11 357 5,432

 RRC District 8 7,440 407 1,217 1,426 409 853 638 0 2 617 8,105

 RRC District 8A 1,289 -47 146 66 15 4 15 0 0 98 1,228

 RRC District 9 11,522 356 1,131 233 97 48 1,212 0 8 775 13,172

 RRC District 10 7,594 -164 1,385 1,061 145 107 1,398 0 0 630 8,484

 State Offshore 164 11 20 56 20 39 0 0 0 27 131

Utah 7,411 -65 893 224 543 7 109 0 0 442 7,146

Virginia 3,091 59 658 560 124 166 97 0 0 172 3,215

West Virginia 6,090 -373 1,058 1,100 916 1,007 1,631 0 66 300 7,163

Wyoming 36,748 538 5,082 5,769 1,331 1,362 2,205 1 0 2,310 36,526

Federal Offshorea 12,856 -55 3,082 2,312 910 1,034 333 71 245 2,224 12,120

 Pacific (California) 740 1 23 10 0 0 0 0 0 29 725

 Gulf of Mexico (Louisiana)a 9,665 -39 2,721 1,841 771 816 193 71 221 1,786 9,250

 Gulf of Mexico (Texas) 2,451 -17 338 461 139 218 140 0 24 409 2,145

Miscellaneousb 349 -75 111 121 14 0 129 0 0 16 363

U.S. Total 283,879 1,292 42,394 38,339 10,582 13,348 46,283 895 1,701 23,224 317,647

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Illinois, Indiana, Maryland, Missouri, Nebraska, Nevada, Oregon, South Dakota, and Tennessee. 

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves," 

They may differ from the official Energy Information Administration production data for natural gas for 2010 contained in the Natural Gas Annual 2010, DOE/EIA-0131(10). 

EIA Natural Gas Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in reserves during 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 21

Table 6. Crude oil plus lease condensate proved reserves, reserves changes, and production 2010

million barrels of 42 U.S. gallons

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 3,566 0 397 76 0 0 30 0 0 195 3,722

Lower 48 States 18,749 188 3,503 1,881 803 1,470 1,736 124 169 1,796 21,459

Alabama 53 12 9 5 3 0 0 1 0 7 60

Arkansas 29 3 12 0 3 0 6 0 0 5 42

California 2,835 14 276 167 1 156 24 0 0 198 2,939

 Coastal Region Onshore 341 0 40 39 1 154 1 0 0 18 478

 Los Angeles Basin Onshore 235 15 22 2 0 1 1 0 0 15 257

 San Joaquin Basin Onshore 2,095 1 204 125 0 1 13 0 0 152 2,037

 State Offshore 164 -2 10 1 0 0 9 0 0 13 167

Colorado 376 25 52 34 3 38 80 0 0 33 501

Florida 9 2 10 0 0 0 0 0 0 2 19

Illinois 66 10 0 4 15 9 2 0 0 4 64

Indiana 8 1 0 0 2 2 0 0 0 1 8

Kansas 264 61 52 47 6 8 5 2 4 41 302

Kentucky 24 -11 1 3 0 6 0 0 0 1 16

Louisiana 480 7 139 93 23 52 28 0 6 66 530

 North 81 -7 69 11 5 12 2 0 0 10 131

 South Onshore 343 13 57 73 7 26 25 0 5 47 342

 State Offshore 56 1 13 9 11 14 1 0 1 9 57

Michigan 52 10 4 5 0 0 0 0 0 6 55

Mississippi 252 25 17 9 8 1 0 0 0 24 254

Montana 343 -4 54 44 115 115 41 2 2 25 369

Nebraska 10 4 1 0 0 0 0 1 0 2 14

New Mexico 780 -2 90 67 22 131 76 0 1 65 922

 East 748 0 85 65 22 131 76 0 1 63 891

 West 32 -2 5 2 0 0 0 0 0 2 31

North Dakota 1,058 -8 709 486 63 226 533 29 3 114 1,887

Ohio 50 22 4 2 37 22 0 0 0 5 54

Oklahoma 802 10 135 106 56 58 146 0 0 63 926

Pennsylvania 17 37 13 12 23 1 4 0 0 3 34

Texas 5,496 -72 846 423 252 469 666 78 8 460 6,356

 RRC District 1 96 -20 16 10 4 9 137 54 0 15 263

 RRC District 2 Onshore 66 -2 14 5 0 2 72 22 0 15 154

 RRC District 3 Onshore 257 26 53 31 42 21 29 2 1 44 272

 RRC District 4 Onshore 92 -3 109 15 2 2 39 0 0 15 207

 RRC District 5 24 1 3 3 0 0 0 0 0 3 22

 RRC District 6 224 3 45 29 5 11 9 0 0 18 240

 RRC District 7B 102 4 9 3 0 0 0 0 0 10 102

 RRC District 7C 509 -10 69 37 56 83 88 0 6 34 618

 RRC District 8 1,985 -93 273 149 116 315 196 0 1 158 2,254

 RRC District 8A 1,790 21 181 66 23 12 15 0 0 108 1,822

 RRC District 9 149 13 11 21 4 10 14 0 0 17 155

 RRC District 10 198 -12 63 54 0 3 67 0 0 22 243

 State Offshore 4 0 0 0 0 1 0 0 0 1 4

Utah 488 13 71 21 24 3 13 0 0 25 518

West Virginia 20 -3 2 0 1 2 2 0 0 1 21

Wyoming 855 25 124 138 81 58 32 1 0 53 823

Federal Offshorea 4,357 -6 879 214 56 108 77 10 145 590 4,710

 Pacific (California) 350 -2 38 4 0 0 0 0 0 19 363

 Gulf of Mexico (Louisiana)a 3,704 -3 790 183 54 102 61 10 134 518 4,043

 Gulf of Mexico (Texas) 303 -1 51 27 2 6 16 0 11 53 304

Miscellaneousb 25 13 3 1 9 5 1 0 0 2 35

U.S. Total 22,315 188 3,900 1,957 803 1,470 1,766 124 169 1,991 25,181

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Missouri, Nevada, New York, South Dakota, Tennessee, and Virginia.

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves." They may

differ from the official Energy Information Administration production data for crude oil and lease condensate for 2010 contained in the Petroleum Supply Annual 2010,

DOE/EIA-0340(10).

EIA Petroleum & Other Liquids Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 22

Table 7. Total U.S. proved reserves of crude oil, natural gas, and lease condensate, 2001-2010

Revisionsa Net of Salesb New Reservoir Provedd Change

Net and and New Field Discoveries Totalc Estimated Reserves from

Adjustments Revisions AdjustmentsAcquisitions Extensions Discoveries in Old Fields DiscoveriesProduction 12/31 Prior Year

Year (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11)

Crude Oil (million barrels of 42 U.S. gallons)

2001 -4 -158 -162 -87 866 1,407 292 2,565 1,915 22,446 401

2002 416 720 1,136 24 492 300 154 946 1,875 22,677 231

2003 163 94 257 -398 426 705 101 1,232 1,877 21,891 -786

2004 74 420 494 23 617 33 132 782 1,819 21,371 -520

2005 221 569 790 278 805 205 41 1,051 1,733 21,757 386

2006 94 2 96 194 504 30 43 577 1,652 20,972 -785

2007 65 1,200 1,265 -19 651 66 73 790 1,691 21,317 345

2008 278 -2,039 -1,761 166 805 142 124 1,071 1,672 19,121 -2,196

2009 -4 1,863 1,859 95 1,155 122 81 1,358 1,751 20,682 1,561

2010 144 1,859 2,003 605 1,495 88 161 1,744 1,767 23,267 2,585

Dry Natural Gas (billion cubic feet, 14.73 psia, 60 degrees Fahrenheit)

2001 2,742 -2,318 424 2,630 16,380 3,578 2,800 22,758 19,779 183,460 6,033

2002 3,727 937 4,664 380 14,769 1,332 1,694 17,795 19,353 186,946 3,486

2003 2,841 -1,638 1,203 1,034 16,454 1,222 1,610 19,286 19,425 189,044 2,098

2004 -114 744 630 1,844 18,198 759 1,206 20,163 19,168 192,513 3,469

2005 1,887 2,699 4,586 2,544 21,050 942 1,208 23,200 18,458 204,385 11,872

2006 743 -1,836 -1,093 2,996 21,778 409 1,155 23,342 18,545 211,085 6,700

2007 1,147 15,461 16,608 408 27,107 796 1,188 29,091 19,466 237,726 26,641

2008 207 -3,128 -2,921 895 26,687 1,170 1,622 29,479 20,523 244,656 6,930

2009 5,098 -1,619 3,479 -141 42,139 1,372 2,598 46,109 21,594 272,509 27,853

2010 509 3,950 4,459 2,595 44,783 850 1,668 47,301 22,239 304,625 32,116

Lease Condensate (million barrels of 42 U.S. gallons)

2001 -57 -188 -245 34 136 73 66 275 218 1,397 -75

2002 7 -38 -31 27 108 18 33 159 207 1,346 -51

2003 29 -103 -74 -18 104 12 36 152 191 1,215 -131

2004 6 24 30 14 114 3 27 144 182 1,221 6

2005 16 -11 5 49 141 4 16 161 174 1,262 41

2006 15 41 56 -5 181 8 19 208 182 1,339 77

2007 -44 75 31 63 214 15 14 243 181 1,495 156

2008 40 -150 -110 21 163 24 13 200 173 1,433 -62

2009 50 145 195 0 150 19 14 183 178 1,633 200

2010 44 84 128 62 271 36 8 315 224 1,914 281

a

 Revisions and adjustments = Col. 1 + Col. 2. 

b Net of sales and acquisitions = acquisitions - sales

c Total discoveries = Col. 5 + Col. 6 + Col. 7. 

d

 Proved reserves = Col. 10 from prior year + Col. 3 + Col. 4 + Col. 8 - Col. 9. 

NA = Not available

Notes: Old means discovered in a prior year. New means discovered during the report year. 

The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves" and Form EIA-64A,

"Annual Report of the Origin of Natural Gas Liquids Production." They may differ from the official EIA production data for crude oil, natural gas, and lease condensate

for 2010 contained in the Petroleum Supply Annual 2010, DOE/EIA-0340(10) and the Natural Gas Annual 2010, DOE/EIA-0131(10). 

EIA Petroleum & Other Liquids Data EIA Natural Gas Data

Sources: U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, 2001 through 2010 annual reports.
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 23

Table 8. Crude oil proved reserves, reserves changes, and production, 2010

million barrels of 42 U.S. gallons

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 3,566 0 397 76 0 0 30 0 0 195 3,722

Lower 48 States 17,116 144 3,032 1,494 725 1,330 1,465 88 161 1,572 19,545

Alabama 37 12 5 5 3 0 0 1 0 5 42

Arkansas 28 2 12 0 3 0 6 0 0 5 40

California 2,835 13 276 167 1 156 24 0 0 198 2,938

 Coastal Region Onshore 341 0 40 39 1 154 1 0 0 18 478

 Los Angeles Basin Onshore 235 15 22 2 0 1 1 0 0 15 257

 San Joaquin Basin Onshore 2,095 0 204 125 0 1 13 0 0 152 2,036

 State Offshore 164 -2 10 1 0 0 9 0 0 13 167

Colorado 279 21 34 17 2 36 61 0 0 26 386

Florida 9 1 10 0 0 0 0 0 0 2 18

Illinois 66 10 0 4 15 9 2 0 0 4 64

Indiana 8 1 0 0 2 2 0 0 0 1 8

Kansas 259 61 49 46 5 5 5 2 4 39 295

Kentucky 20 -11 1 0 0 6 0 0 0 1 15

Louisiana 370 -5 120 60 17 41 24 0 3 52 424

 North 55 -9 67 8 1 6 1 0 0 7 104

 South Onshore 269 5 42 45 5 21 22 0 2 37 274

 State Offshore 46 -1 11 7 11 14 1 0 1 8 46

Michigan 33 10 3 1 0 0 0 0 0 5 40

Mississippi 244 22 17 6 8 1 0 0 0 23 247

Montana 343 -4 54 44 115 115 41 2 2 25 369

Nebraska 9 0 1 0 0 0 0 1 0 1 10

New Mexico 700 -10 74 56 21 120 73 0 1 58 823

 East 688 -7 72 56 21 120 73 0 1 57 813

 West 12 -3 2 0 0 0 0 0 0 1 10

North Dakota 1,046 -8 672 474 63 190 532 29 3 113 1,814

Ohio 38 26 2 0 37 17 0 0 0 4 42

Oklahoma 622 -4 89 52 55 56 98 0 0 44 710

Pennsylvania 10 33 9 6 23 1 0 0 0 2 22

Texas 5,006 -54 657 315 234 421 499 44 7 357 5,674

 RRC District 1 82 -15 14 7 0 5 121 42 0 14 228

 RRC District 2 Onshore 51 -3 10 1 0 2 57 1 0 10 107

 RRC District 3 Onshore 183 28 34 15 38 9 19 1 0 24 197

 RRC District 4 Onshore 18 -2 97 1 0 0 2 0 0 3 111

 RRC District 5 16 1 3 2 0 0 0 0 0 2 16

 RRC District 6 129 2 22 12 2 3 5 0 0 11 136

 RRC District 7B 97 4 8 2 0 0 0 0 0 9 98

 RRC District 7C 475 -8 63 31 54 81 74 0 6 30 576

 RRC District 8 1,956 -90 222 143 115 299 166 0 1 120 2,176

 RRC District 8A 1,780 24 151 60 23 12 14 0 0 108 1,790

 RRC District 9 124 13 8 14 2 8 12 0 0 15 134

 RRC District 10 94 -8 25 27 0 1 29 0 0 11 103

 State Offshore 1 0 0 0 0 1 0 0 0 0 2

Utah 398 10 65 18 0 3 13 0 0 22 449

West Virginia 19 -4 1 0 1 2 1 0 0 1 17

Wyoming 583 17 58 45 68 46 15 1 0 40 567

Federal Offshorea 4,129 -8 820 177 43 98 70 8 141 542 4,496

 Pacific (California) 348 -2 38 4 0 0 0 0 0 19 361

 Gulf of Mexico (Louisiana)a 3,570 -6 746 155 41 92 57 8 133 490 3,914

 Gulf of Mexico (Texas) 211 0 36 18 2 6 13 0 8 33 221

Miscellaneousb 25 13 3 1 9 5 1 0 0 2 35

U.S. Total 20,682 144 3,429 1,570 725 1,330 1,495 88 161 1,767 23,267

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Missouri, Nevada, New York, South Dakota, Tennessee, and Virginia.

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves." They may

differ from the official Energy Information Administration production data for crude oil for 2010 contained in the Petroleum Supply Annual 2010,

DOE/EIA-0340(10).

EIA Petroleum & Other Liquids Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 24

Table 9. Dry natural gas proved reserves, reserves changes, and production, 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 9,101 1 622 452 131 0 14 0 0 317 8,838

Lower 48 States 263,408 508 39,899 36,119 10,022 12,748 44,769 850 1,668 21,922 295,787

Alabama 2,871 32 206 173 263 148 28 3 0 223 2,629

Arkansas 10,869 -34 1,072 301 393 807 3,082 0 27 951 14,178

California 2,773 10 548 451 3 0 12 1 0 243 2,647

 Coastal Region Onshore 163 1 38 16 1 0 0 0 0 12 173

 Los Angeles Basin Onshore 84 5 9 5 0 0 0 0 0 6 87

 San Joaquin Basin Onshore 2,469 4 488 427 2 0 8 1 0 220 2,321

 State Offshore 57 0 13 3 0 0 4 0 0 5 66

Colorado 23,058 449 2,973 3,645 242 229 2,838 22 27 1,590 24,119

Florida 7 64 0 0 0 0 0 0 0 15 56

Kansas 3,279 140 687 166 17 23 27 4 1 305 3,673

Kentucky 2,782 -58 103 540 0 39 383 0 0 96 2,613

Louisiana 20,688 -612 3,149 3,184 738 847 10,989 48 279 2,189 29,277

 North 17,143 -387 2,593 2,485 602 562 10,707 47 173 1,721 26,030

 South Onshore 2,844 3 490 615 69 243 280 1 93 394 2,876

 State Offshore 701 -228 66 84 67 42 2 0 13 74 371

Michigan 2,763 243 260 378 529 711 1 2 0 154 2,919

Mississippi 917 1 77 70 31 13 33 0 0 87 853

Montana 976 -19 103 100 40 30 86 0 1 93 944

New Mexico 15,598 -89 2,211 1,833 145 419 468 0 3 1,220 15,412

 East 4,141 -200 480 418 133 419 326 0 3 392 4,226

 West 11,457 111 1,731 1,415 12 0 142 0 0 828 11,186

New York 196 104 35 83 2 11 0 56 0 36 281

North Dakota 1,079 -2 848 722 47 136 442 25 2 94 1,667

Ohio 896 127 68 59 374 239 8 0 0 73 832

Oklahoma 22,769 -394 3,224 3,474 219 1,519 4,571 51 1 1,703 26,345

Pennsylvania 6,985 -373 2,892 1,938 678 930 5,779 50 904 591 13,960

Texas 80,424 985 10,917 9,252 2,580 3,179 11,657 519 122 6,974 88,997

 RRC District 1 1,398 -95 424 320 466 416 1,023 117 15 113 2,399

 RRC District 2 Onshore 1,800 -10 333 302 18 30 178 307 9 237 2,090

 RRC District 3 Onshore 2,616 82 482 319 184 199 175 20 25 508 2,588

 RRC District 4 Onshore 6,728 3 1,084 850 208 180 943 24 3 893 7,014

 RRC District 5 22,343 27 1,577 1,274 1 5 3,457 0 0 1,771 24,363

 RRC District 6 12,795 403 2,660 2,680 505 955 2,173 51 51 1,017 14,886

 RRC District 7B 2,077 68 260 231 3 0 220 0 0 149 2,242

 RRC District 7C 4,827 68 535 710 575 451 496 0 10 315 4,787

 RRC District 8 6,672 304 1,082 1,268 363 758 568 0 2 549 7,206

 RRC District 8A 1,218 -40 138 63 14 4 14 0 0 93 1,164

 RRC District 9 10,904 336 1,070 221 92 46 1,147 0 7 733 12,464

 RRC District 10 6,882 -172 1,252 958 131 96 1,263 0 0 569 7,663

 State Offshore 164 11 20 56 20 39 0 0 0 27 131

Utah 7,257 -80 872 219 530 7 106 0 0 432 6,981

Virginia 3,091 59 658 560 124 166 97 0 0 172 3,215

West Virginia 5,946 -359 1,034 1,075 895 984 1,594 0 64 293 7,000

Wyoming 35,283 521 4,880 5,540 1,278 1,308 2,117 1 0 2,218 35,074

Federal Offshorea 12,552 -123 2,978 2,242 880 1,003 326 68 237 2,154 11,765

 Pacific (California) 739 0 23 10 0 0 0 0 0 28 724

 Gulf of Mexico (Louisiana)a 9,362 -106 2,617 1,771 741 785 186 68 213 1,717 8,896

 Gulf of Mexico (Texas) 2,451 -17 338 461 139 218 140 0 24 409 2,145

Miscellaneousb 349 -84 104 114 14 0 125 0 0 16 350

U.S. Total 272,509 509 40,521 36,571 10,153 12,748 44,783 850 1,668 22,239 304,625

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Illinois, Indiana, Maryland, Missouri, Nebraska, Nevada, Oregon, South Dakota, and Tennessee. 

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves," 

and Form EIA-64A, "Annual Report of the Origin of Natural Gas Liquids Production." They may differ from the official Energy Information 

Administration production data for natural gas for 2010 contained in the Natural Gas Annual 2010, DOE/EIA-0131(10). 

EIA Natural Gas Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 25

Table 10. Lease condensate proved reserves, reserves changes, and production, 2010

million barrels of 42 U.S. gallons

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 0 0 0 0 0 0 0 0 0 0 0

Lower 48 States 1,633 44 471 387 78 140 271 36 8 224 1,914

Alabama 16 0 4 0 0 0 0 0 0 2 18

Arkansas 1 1 0 0 0 0 0 0 0 0 2

California 0 1 0 0 0 0 0 0 0 0 1

 Coastal Region Onshore 0 0 0 0 0 0 0 0 0 0 0

 Los Angeles Basin Onshore 0 0 0 0 0 0 0 0 0 0 0

 San Joaquin Basin Onshore 0 1 0 0 0 0 0 0 0 0 1

 State Offshore 0 0 0 0 0 0 0 0 0 0 0

Colorado 97 4 18 17 1 2 19 0 0 7 115

Florida 0 1 0 0 0 0 0 0 0 0 1

Kansas 5 0 3 1 1 3 0 0 0 2 7

Kentucky 4 0 0 3 0 0 0 0 0 0 1

Louisiana 110 12 19 33 6 11 4 0 3 14 106

 North 26 2 2 3 4 6 1 0 0 3 27

 South Onshore 74 8 15 28 2 5 3 0 3 10 68

 State Offshore 10 2 2 2 0 0 0 0 0 1 11

Michigan 19 0 1 4 0 0 0 0 0 1 15

Mississippi 8 3 0 3 0 0 0 0 0 1 7

Montana 0 0 0 0 0 0 0 0 0 0 0

New Mexico 80 8 16 11 1 11 3 0 0 7 99

 East 60 7 13 9 1 11 3 0 0 6 78

 West 20 1 3 2 0 0 0 0 0 1 21

North Dakota 12 0 37 12 0 36 1 0 0 1 73

Oklahoma 180 14 46 54 1 2 48 0 0 19 216

Texas 490 -18 189 108 18 48 167 34 1 103 682

 RRC District 1 14 -5 2 3 4 4 16 12 0 1 35

 RRC District 2 Onshore 15 1 4 4 0 0 15 21 0 5 47

 RRC District 3 Onshore 74 -2 19 16 4 12 10 1 1 20 75

 RRC District 4 Onshore 74 -1 12 14 2 2 37 0 0 12 96

 RRC District 5 8 0 0 1 0 0 0 0 0 1 6

 RRC District 6 95 1 23 17 3 8 4 0 0 7 104

 RRC District 7B 5 0 1 1 0 0 0 0 0 1 4

 RRC District 7C 34 -2 6 6 2 2 14 0 0 4 42

 RRC District 8 29 -3 51 6 1 16 30 0 0 38 78

 RRC District 8A 10 -3 30 6 0 0 1 0 0 0 32

 RRC District 9 25 0 3 7 2 2 2 0 0 2 21

 RRC District 10 104 -4 38 27 0 2 38 0 0 11 140

 State Offshore 3 0 0 0 0 0 0 0 0 1 2

Utah 90 3 6 3 24 0 0 0 0 3 69

West Virginia 1 1 1 0 0 0 1 0 0 0 4

Wyoming 272 8 66 93 13 12 17 0 0 13 256

Federal Offshorea 228 2 59 37 13 10 7 2 4 48 214

 Pacific (California) 2 0 0 0 0 0 0 0 0 0 2

 Gulf of Mexico (Louisiana)a 134 3 44 28 13 10 4 2 1 28 129

 Gulf of Mexico (Texas) 92 -1 15 9 0 0 3 0 3 20 83

Miscellaneousb 20 4 6 8 0 5 4 0 0 3 28

U.S. Total 1,633 44 471 387 78 140 271 36 8 224 1,914

a

 Includes Federal Offshore Alabama

b

 Includes Arizona, Nebraska, Nevada, New York, Ohio, Pennsylvania, South Dakota, Tennessee, and Virginia.

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves." They may

differ from the official Energy Information Administration production data for crude oil for 2010 contained in the Petroleum Supply Annual 2010,

DOE/EIA-0340(10).

EIA Petroleum & Other Liquids Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 26

Table 11. Nonassociated natural gas proved reserves, reserves changes, and production, wet after 

lease separation, 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases SalesAcquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 1,090 -2 392 195 132 0 13 0 0 145 1,021

Lower 48 States 249,406 1,776 37,019 34,180 9,304 10,879 43,610 793 1,515 20,634 280,880

Alabama 2,919 47 208 176 270 153 29 1 0 225 2,686

Arkansas 10,852 -31 1,060 301 393 807 3,079 0 27 948 14,152

California 612 -3 50 87 2 0 1 1 0 69 503

 Coastal Region Onshore 1 0 1 0 0 0 0 0 0 0 2

 Los Angeles Basin Onshore 0 0 0 0 0 0 0 0 0 0 0

 San Joaquin Basin Onshore 607 -3 47 84 2 0 0 1 0 68 498

 State Offshore 4 0 2 3 0 0 1 0 0 1 3

Colorado 22,199 578 2,985 3,763 253 81 2,668 23 29 1,546 23,001

Florida 0 33 0 0 0 0 0 0 0 7 26

Kansas 3,417 168 718 163 17 21 26 3 1 316 3,858

Kentucky 2,887 -17 40 576 0 34 408 0 0 102 2,674

Louisiana 19,898 -411 3,039 3,051 658 792 11,019 49 268 2,107 28,838

 North 17,220 -484 2,594 2,489 598 564 10,751 48 173 1,716 26,063

 South Onshore 2,463 -42 399 498 55 205 266 1 95 338 2,496

 State Offshore 215 115 46 64 5 23 2 0 0 53 279

Michigan 2,728 254 255 372 539 725 1 2 0 151 2,903

Mississippi 884 -8 67 59 25 11 33 0 0 81 822

Montana 681 16 65 70 12 0 47 0 0 70 657

New Mexico 14,662 71 2,134 1,711 104 150 244 0 1 1,131 14,316

 East 2,658 -49 339 225 91 150 94 0 1 265 2,612

 West 12,004 120 1,795 1,486 13 0 150 0 0 866 11,704

New York 196 104 35 83 2 0 0 56 0 35 271

North Dakota 143 -5 245 264 2 24 21 0 0 10 152

Ohio 799 184 63 58 374 185 8 0 0 65 742

Oklahoma 23,115 -93 3,271 3,613 164 1,535 4,492 54 1 1,725 26,873

Pennsylvania 6,885 -303 2,904 1,935 683 855 5,824 51 911 585 13,924

Texas 76,272 1,057 10,189 8,835 2,075 2,254 11,332 488 116 6,641 84,157

 RRC District 1 1,456 -95 430 331 505 445 960 63 16 107 2,332

 RRC District 2 Onshore 1,837 18 321 308 19 29 123 327 10 237 2,101

 RRC District 3 Onshore 2,326 56 419 288 157 202 181 21 27 479 2,308

 RRC District 4 Onshore 6,961 38 1,129 882 219 189 984 25 3 927 7,301

 RRC District 5 22,602 65 1,596 1,290 1 5 3,504 0 0 1,795 24,686

 RRC District 6 12,806 400 2,732 2,739 523 985 2,213 52 52 1,020 14,958

 RRC District 7B 2,322 48 295 256 3 0 258 0 0 160 2,504

 RRC District 7C 3,724 84 380 714 261 173 358 0 0 242 3,502

 RRC District 8 3,950 229 642 894 124 48 262 0 0 336 3,777

 RRC District 8A 43 20 5 7 3 0 8 0 0 8 58

 RRC District 9 11,100 345 932 223 95 44 1,207 0 8 731 12,587

 RRC District 10 6,984 -144 1,288 868 145 99 1,274 0 0 573 7,915

 State Offshore 161 -7 20 35 20 35 0 0 0 26 128

Utah 6,810 -50 776 163 543 1 89 0 0 405 6,515

Virginia 3,091 59 658 560 124 166 97 0 0 172 3,215

West Virginia 6,066 -370 1,055 1,098 909 993 1,628 0 66 297 7,134

Wyoming 36,386 542 5,038 5,688 1,314 1,308 2,191 0 0 2,271 36,192

Federal Offshorea 7,633 -41 2,054 1,433 827 784 246 65 95 1,660 6,916

 Pacific (California) 9 0 0 5 0 0 0 0 0 1 3

 Gulf of Mexico (Louisiana)a 5,802 -25 1,814 1,000 697 594 139 65 83 1,318 5,457

 Gulf of Mexico (Texas) 1,822 -16 240 428 130 190 107 0 12 341 1,456

Miscellaneousb 271 -5 110 121 14 0 127 0 0 15 353

U.S. Total 250,496 1,774 37,411 34,375 9,436 10,879 43,623 793 1,515 20,779 281,901

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Illinois, Indiana, Maryland, Missouri, Nebraska, Nevada, Oregon, South Dakota, and Tennessee. 

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves," 

They may differ from the official Energy Information Administration production data for natural gas for 2010 contained in the Natural Gas Annual 2010, 

DOE/EIA-0131(10). 

EIA Natural Gas Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 27

Table 12. Associated-dissolved natural gas proved reserves, reserves changes, and production, wet 

after lease separation, 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 8,093 -1 236 260 0 0 2 0 0 174 7,896

Lower 48 States 25,290 -481 4,747 3,704 1,146 2,469 2,658 102 186 2,271 27,850

Alabama 29 13 6 4 2 0 0 2 0 6 38

Arkansas 20 -3 12 0 0 0 4 0 0 4 29

California 2,314 7 525 389 1 0 12 0 0 186 2,282

 Coastal Region Onshore 168 2 38 17 1 0 0 0 0 12 178

 Los Angeles Basin Onshore 91 3 9 5 0 0 0 0 0 6 92

 San Joaquin Basin Onshore 2,002 2 467 367 0 0 9 0 0 164 1,949

 State Offshore 53 0 11 0 0 0 3 0 0 4 63

Colorado 1,882 68 142 71 2 160 318 0 0 126 2,371

Florida 7 31 0 0 0 0 0 0 0 8 30

Kansas 83 -2 18 15 1 3 3 1 0 11 79

Kentucky 32 2 70 0 0 8 0 0 0 1 111

Louisiana 1,072 -282 144 171 88 69 26 0 17 108 679

 North 53 33 10 6 6 0 0 0 1 12 73

 South Onshore 506 37 111 142 17 48 26 0 2 72 499

 State Offshore 513 -352 23 23 65 21 0 0 14 24 107

Michigan 77 4 10 13 0 0 0 0 0 6 72

Mississippi 38 11 10 12 6 2 0 0 0 7 36

Montana 312 -38 40 31 29 30 41 0 1 24 302

New Mexico 1,982 -103 230 249 57 319 270 0 2 181 2,213

 East 1,900 -110 198 241 57 319 270 0 2 173 2,108

 West 82 7 32 8 0 0 0 0 0 8 105

New York 0 0 0 0 0 11 0 0 0 1 10

North Dakota 1,070 0 705 546 51 128 475 28 3 95 1,717

Ohio 97 -57 5 1 0 54 0 0 0 8 90

Oklahoma 1,092 -178 177 103 70 90 398 0 0 97 1,309

Pennsylvania 133 -54 10 18 0 83 0 0 0 10 144

Texas 8,762 206 1,450 1,058 732 1,188 985 64 13 748 10,130

 RRC District 1 67 -15 29 16 0 6 148 63 0 15 267

 RRC District 2 Onshore 72 -13 35 15 0 3 67 1 0 16 134

 RRC District 3 Onshore 476 34 98 54 40 11 7 0 0 66 466

 RRC District 4 Onshore 96 -1 14 13 1 1 9 0 0 14 91

 RRC District 5 21 -12 2 2 0 0 0 0 0 1 8

 RRC District 6 451 13 23 37 0 4 37 0 0 33 458

 RRC District 7B 102 39 9 14 0 0 0 0 0 15 121

 RRC District 7C 1,706 41 228 92 392 338 205 0 11 115 1,930

 RRC District 8 3,490 178 575 532 285 805 376 0 2 281 4,328

 RRC District 8A 1,246 -67 141 59 12 4 7 0 0 90 1,170

 RRC District 9 422 11 199 10 2 4 5 0 0 44 585

 RRC District 10 610 -20 97 193 0 8 124 0 0 57 569

 State Offshore 3 18 0 21 0 4 0 0 0 1 3

Utah 601 -15 117 61 0 6 20 0 0 37 631

West Virginia 24 -3 3 2 7 14 3 0 0 3 29

Wyoming 362 -4 44 81 17 54 14 1 0 39 334

Federal Offshorea 5,223 -14 1,028 879 83 250 87 6 150 564 5,204

 Pacific (California) 731 1 23 5 0 0 0 0 0 28 722

 Gulf of Mexico (Louisiana)a 3,863 -14 907 841 74 222 54 6 138 468 3,793

 Gulf of Mexico (Texas) 629 -1 98 33 9 28 33 0 12 68 689

Miscellaneousb 78 -70 1 0 0 0 2 0 0 1 10

U.S. Total 33,383 -482 4,983 3,964 1,146 2,469 2,660 102 186 2,445 35,746

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Illinois, Indiana, Maryland, Missouri, Nebraska, Nevada, Oregon, South Dakota, Tennessee, and Virginia. 

Note: The production estimates in this table are based on data reported on Form EIA-23, "Annual Survey of Domestic Oil and Gas Reserves," 

They may differ from the official Energy Information Administration production data for natural gas for 2010 contained in the Natural Gas Annual 2010, 

DOE/EIA-0131(10). 

EIA Natural Gas Data

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 28

Table 13. Shale natural gas proved reserves and production, 2007 – 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

State and Subdivision 2007 2008 2009 2010 2007 2008 2009 2010

Alaska 0 0 0 0 0 0 0 0

Lower 48 States 23,304 34,428 60,644 97,449 1,293 2,116 3,110 5,336

Alabama 1 2 0 0 0 0 0 0

Arkansas 1,460 3,833 9,070 12,526 94 279 527 794

California 0 0 0 0 0 0 0 0

Colorado 0 0 4 4 0 0 1 1

Florida 0 0 0 0 0 0 0 0

Kansas 0 0 0 0 0 0 0 0

Kentucky 21 20 55 10 2 2 5 4

Louisiana 6 858 9,307 20,070 1 23 293 1,232

 North 6 858 9,307 20,070 1 23 293 1,232

 South 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0

Michigan 3,281 2,894 2,499 2,306 148 122 132 120

Mississippi 0 0 0 0 0 0 0 0

Montana 140 125 137 186 12 13 7 13

New Mexico 12 0 36 123 2 0 2 6

 East 12 0 7 35 2 0 1 3

 West 0 0 29 88 0 0 1 3

New York 0 0 0 0 0 0 0 0

North Dakota 21 24 368 1,185 3 3 25 64

Ohio 0 0 0 0 0 0 0 0

Oklahoma 944 3,845 6,389 9,670 40 168 249 403

Pennsylvania 96 88 3,790 10,708 1 1 65 396

Texas 17,256 22,667 28,167 38,048 988 1,503 1,789 2,218

 RRC District 1 0 2 435 1,564 0 0 11 41

 RRC District 2 Onshore 0 0 0 395 0 0 0 7

 RRC District 3 Onshore 0 0 0 0 0 0 0 0

 RRC District 4 Onshore 0 0 78 565 0 0 5 26

 RRC District 5 8,099 11,408 13,691 16,032 437 769 954 1,053

 RRC District 6 0 173 1,161 4,381 0 3 28 219

 RRC District 7B 2,018 2,336 2,022 2,435 90 141 145 140

 RRC District 7C 0 0 0 13 0 0 0 0

 RRC District 8 5 48 24 90 1 4 3 7

 RRC District 8A 0 0 0 0 0 0 0 0

 RRC District 9 7,134 8,700 10,756 12,573 460 586 643 725

 RRC District 10 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0

Utah 0 0 0 0 0 0 0 0

Virginia 0 0 0 0 0 0 0 0

West Virginia 0 14 688 2,491 0 0 11 80

Wyoming 0 0 0 1 0 0 0 0

Federal Offshore 0 0 0 0 0 0 0 0

Miscellaneousa 66 58 134 121 2 2 4 9

U.S. Total 23,304 34,428 60,644 97,449 1,293 2,116 3,110 5,336

a

 Includes Indiana, Missouri, and Tennessee.

Note: The above table is based on shale natural gas proved reserves and production volumes reported and imputed from data

on Form EIA-23 "Annual Survey of Domestic Oil and Gas Reserves." For certain reasons (e.g. incorrect or incomplete respondent submissions,

respondent mis-identification of shale vs non-shale reservoirs) the actual proved reserves and production of natural gas

from shales may be higher or lower. The production estimates are offered only as an observed indicator of production trends and may differ 

from official EIA production volumes listed elsewhere on the EIA web page.

Sources: U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, 2007 through 2010 annual reports, DOE/EIA-0216.

Reserves Production
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 29

Table 14. Shale natural gas proved reserves, reserves changes, and production, wet after lease 

separation, 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old FieldsProduction Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 0 0 0 0 0 0 0 0 0 0 0

Lower 48 States 60,644 7,579 10,661 9,491 1,685 4,290 29,081 557 1,149 5,336 97,449

Alabama 0 0 0 0 0 0 0 0 0 0 0

Arkansas 9,070 63 861 126 336 774 3,014 0 0 794 12,526

California 0 0 0 0 0 0 0 0 0 0 0

Colorado 4 -1 1 2 0 0 3 0 0 1 4

Florida 0 0 0 0 0 0 0 0 0 0 0

Kansas 0 0 0 0 0 0 0 0 0 0 0

Kentucky 55 -1 3 43 0 0 0 0 0 4 10

Louisiana 9,307 2,347 1,856 1,878 11 115 9,346 48 172 1,232 20,070

 North Onshore 9,307 2,347 1,856 1,878 11 115 9,346 48 172 1,232 20,070

 South Onshore 0 0 0 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0 0 0 0

Michigan 2,499 305 165 325 553 333 0 2 0 120 2,306

Mississippi 0 0 0 0 0 0 0 0 0 0 0

Montana 137 40 14 16 1 0 25 0 0 13 186

New Mexico 36 3 1 11 0 0 100 0 0 6 123

 East 7 3 1 2 0 0 29 0 0 3 35

 West 29 0 0 9 0 0 71 0 0 3 88

New York 0 0 0 0 0 0 0 0 0 0 0

North Dakota 368 235 528 343 28 87 393 8 1 64 1,185

Ohio 0 0 0 0 0 0 0 0 0 0 0

Oklahoma 6,389 713 1,352 2,117 0 1,302 2,380 54 0 403 9,670

Pennsylvania 3,790 235 1,994 1,583 163 757 5,154 49 871 396 10,708

Texas 28,167 2,940 3,580 2,425 580 594 7,558 396 36 2,218 38,048

 RRC District 1 435 8 322 251 409 401 971 114 14 41 1,564

 RRC District 2 Onshore 0 6 6 5 0 2 109 282 2 7 395

 RRC District 3 Onshore 0 0 0 0 0 0 0 0 0 0 0

 RRC District 4 Onshore 78 0 66 12 0 0 459 0 0 26 565

 RRC District 5 13,691 105 643 405 0 6 3,045 0 0 1,053 16,032

 RRC District 6 1,161 1,968 1,206 1,319 88 150 1,520 0 2 219 4,381

 RRC District 7B 2,022 267 273 242 0 0 255 0 0 140 2,435

 RRC District 7C 0 0 0 0 0 3 0 0 10 0 13

 RRC District 8 24 53 20 0 0 0 0 0 0 7 90

 RRC District 8A 0 0 0 0 0 0 0 0 0 0 0

 RRC District 9 10,756 533 1,044 191 83 32 1,199 0 8 725 12,573

 RRC District 10 0 0 0 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0 0 0 0

Utah 0 0 0 0 0 0 0 0 0 0 0

Virginia 0 0 0 0 0 0 0 0 0 0 0

West Virginia 688 701 289 543 2 324 1,045 0 69 80 2,491

Wyoming 0 -1 0 2 0 4 0 0 0 0 1

Federal Offshore 0 0 0 0 0 0 0 0 0 0 0

Miscellaneousa 134 0 17 77 11 0 63 0 0 5 121

U.S. Total 60,644 7,579 10,661 9,491 1,685 4,290 29,081 557 1,149 5,336 97,449

a

 Includes Indiana, Missouri, and Tennessee.

Note: The above table is based on shale natural gas proved reserves and production volumes reported and imputed from data

on Form EIA-23 "Annual Survey of Domestic Oil and Gas Reserves." For certain reasons (e.g. incorrect or incomplete respondent submissions,

respondent mis-identification of shale vs non-shale reservoirs) the actual proved reserves and production of natural gas

from shales may be higher or lower. The production estimates are offered only as an observed indicator of production trends and may differ 

from official EIA production volumes listed elsewhere on the EIA web page.

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 30

Table 15. Coalbed methane proved reserves and production, 2006 – 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

State and Subdivision 2006 2007 2008 2009 2010 2006 2007 2008 2009 2010

Alaska 0 0 0 0 0 0 0 0 0 0

Lower 48 States 19,620 21,874 20,798 18,578 17,508 1,758 1,753 1,966 1,914 1,886

Alabama 2,068 2,126 1,727 1,342 1,298 114 114 107 105 102

Arkansas 34 31 31 22 28 3 3 3 3 3

California 0 0 0 0 0 0 0 0 0 0

Colorado 6,344 7,869 8,238 7,348 6,485 477 519 497 498 533

Florida 0 0 0 0 0 0 0 0 0 0

Kansas 234 340 301 163 258 25 38 47 43 41

Kentucky 0 0 0 0 0 0 0 0 0 0

Louisiana 1 7 9 0 0 0 0 1 1 0

 North 1 7 9 0 0 0 0 1 1 0

 South Onshore 0 0 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0 0 0

Michigan 0 0 0 0 0 0 0 0 0 0

Mississippi 0 0 0 0 0 0 0 0 0 0

Montana 77 66 75 37 64 12 13 14 12 10

New Mexico 4,894 4,169 3,991 3,646 3,532 510 394 443 432 402

 East 322 389 530 474 523 26 23 23 26 27

 West 4,572 3,780 3,461 3,172 3,009 484 371 420 406 375

New York 0 0 0 0 0 0 0 0 0 0

North Dakota 0 0 0 0 0 0 0 0 0 0

Ohio 1 1 1 0 0 0 0 0 0 0

Oklahoma 684 1,265 511 338 325 68 82 69 55 45

Pennsylvania 50 108 102 131 129 5 5 11 16 3

Texas 0 0 0 0 0 0 0 0 0 0

 RRC District 1 0 0 0 0 0 0 0 0 0 0

 RRC District 2 Onshore 0 0 0 0 0 0 0 0 0 0

 RRC District 3 Onshore 0 0 0 0 0 0 0 0 0 0

 RRC District 4 Onshore 0 0 0 0 0 0 0 0 0 0

 RRC District 5 0 0 0 0 0 0 0 0 0 0

 RRC District 6 0 0 0 0 0 0 0 0 0 0

 RRC District 7B 0 0 0 0 0 0 0 0 0 0

 RRC District 7C 0 0 0 0 0 0 0 0 0 0

 RRC District 8 0 0 0 0 0 0 0 0 0 0

 RRC District 8A 0 0 0 0 0 0 0 0 0 0

 RRC District 9 0 0 0 0 0 0 0 0 0 0

 RRC District 10 0 0 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0 0 0

Utah 750 922 893 725 718 66 73 71 71 66

Virginia 1,813 1,948 1,851 2,261 1,752 81 85 101 111 97

West Virginia 194 255 246 220 220 18 25 28 31 17

Wyoming 2,448 2,738 2,781 2,328 2,683 378 401 573 535 566

Federal Offshore 0 0 0 0 0 0 0 0 0 0

Miscellaneousa 28 29 41 17 16 1 1 1 1 1

U.S. Total 19,620 21,874 20,798 18,578 17,508 1,758 1,753 1,966 1,914 1,886

a

 Includes Illinois and Indiana.

Sources: U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Reserves, 2006 through 2010 annual reports, DOE/EIA-0216.

Reserves Production
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 31

Table 16. Coalbed methane proved reserves, reserves changes, and production, 2010

billion cubic feet at 14.73 psia and 60 degrees Fahrenheit

Published New Reservoir

Proved Revision Revision New Field Discoveries Estimated Proved

Reserves Adjustments Increases Decreases Sales Acquisitions Extensions Discoveries in Old Fields Production Reserves

State and Subdivision 12/31/09 (+,-) (+) (-) (-) (+) (+) (+) (+) (-) 12/31/10

Alaska 0 0 0 0 0 0 0 0 0 0 0

Lower 48 States 18,578 784 2,589 2,914 366 226 497 0 0 1,886 17,508

Alabama 1,342 61 134 51 266 151 29 0 0 102 1,298

Arkansas 22 1 9 1 0 0 0 0 0 3 28

California 0 0 0 0 0 0 0 0 0 0 0

Colorado 7,348 106 937 1,557 0 0 184 0 0 533 6,485

Florida 0 0 0 0 0 0 0 0 0 0 0

Kansas 163 -22 157 0 0 0 1 0 0 41 258

Kentucky 0 0 0 0 0 0 0 0 0 0 0

Louisiana 0 0 0 0 0 0 0 0 0 0 0

 North Onshore 0 0 0 0 0 0 0 0 0 0 0

 South Onshore 0 0 0 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0 0 0 0

Michigan 0 0 0 0 0 0 0 0 0 0 0

Mississippi 0 0 0 0 0 0 0 0 0 0 0

Montana 37 11 23 0 0 0 3 0 0 10 64

New Mexico 3,646 261 562 565 12 0 42 0 0 402 3,532

 East 474 4 72 0 0 0 0 0 0 27 523

 West 3,172 257 490 565 12 0 42 0 0 375 3,009

New York 0 0 0 0 0 0 0 0 0 0 0

North Dakota 0 0 0 0 0 0 0 0 0 0 0

Ohio 0 0 0 0 0 0 0 0 0 0 0

Oklahoma 338 27 82 84 6 11 2 0 0 45 325

Pennsylvania 131 -1 2 0 0 0 0 0 0 3 129

Texas 0 0 0 0 0 0 0 0 0 0 0

 RRC District 1 0 0 0 0 0 0 0 0 0 0 0

 RRC District 2 Onshore 0 0 0 0 0 0 0 0 0 0 0

 RRC District 3 Onshore 0 0 0 0 0 0 0 0 0 0 0

 RRC District 4 Onshore 0 0 0 0 0 0 0 0 0 0 0

 RRC District 5 0 0 0 0 0 0 0 0 0 0 0

 RRC District 6 0 0 0 0 0 0 0 0 0 0 0

 RRC District 7B 0 0 0 0 0 0 0 0 0 0 0

 RRC District 7C 0 0 0 0 0 0 0 0 0 0 0

 RRC District 8 0 0 0 0 0 0 0 0 0 0 0

 RRC District 8A 0 0 0 0 0 0 0 0 0 0 0

 RRC District 9 0 0 0 0 0 0 0 0 0 0 0

 RRC District 10 0 0 0 0 0 0 0 0 0 0 0

 State Offshore 0 0 0 0 0 0 0 0 0 0 0

Utah 725 8 77 30 0 0 4 0 0 66 718

Virginia 2,261 1 16 459 0 0 30 0 0 97 1,752

West Virginia 220 0 15 25 0 5 22 0 0 17 220

Wyoming 2,328 329 575 140 82 59 180 0 0 566 2,683

Federal Offshore 0 0 0 0 0 0 0 0 0 0 0

Miscellaneousa 17 2 0 2 0 0 0 0 0 1 16

U.S. Total 18,578 784 2,589 2,914 366 226 497 0 0 1,886 17,508

a

 Includes Illinois and Indiana.

Source: U.S. Energy Information Administration, Form EIA-23

Changes in Reserves During 2010
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 32

Table 17. Natural gas plant liquids proved reserves and production, 2009 – 2010 (excludes lease 

condensate)

million barrels of 42 U.S. gallons

Reserves Production

State and Subdivision 2009 2010 2009 2010

Alaska 299 288 13 11

Lower 48 States 8,258 9,521 701 734

Alabama 55 68 5 6

Arkansas 2 2 0 0

California 129 114 11 10

 Coastal Region Onshore 10 11 1 1

 Los Angeles Basin Onshore 6 5 0 0

 San Joaquin Basin Onshore 113 98 10 9

 State Offshore 0 0 0 0

Colorado 722 879 48 58

Florida 0 0 0 0

Kansas 162 195 16 16

Kentucky 101 124 4 5

Louisiana 231 216 26 25

 North 98 79 6 5

 South Onshore 90 113 15 15

 State Offshore 43 24 5 5

Michigan 43 48 2 3

Mississippi 4 4 0 0

Montana 12 11 1 1

New Mexico 715 764 65 63

 East 289 342 32 32

 West 426 422 33 31

North Dakota 104 157 8 9

Oklahoma 985 1,270 77 82

Pennsylvania 25 81 1 3

Texas 3,432 3,983 300 311

 RRC District 1 87 163 5 8

 RRC District 2 Onshore 77 113 11 13

 RRC District 3 Onshore 127 129 25 25

 RRC District 4 Onshore 231 258 35 33

 RRC District 5 192 225 15 16

 RRC District 6 330 369 26 25

 RRC District 7B 326 359 27 24

 RRC District 7C 412 465 28 31

 RRC District 8 536 618 44 47

 RRC District 8A 201 230 18 18

 RRC District 9 419 488 26 29

 RRC District 10 494 566 40 42

 State Offshore 0 0 0 0

Utah 116 132 7 8

West Virginia 108 122 5 5

Wyoming 1,010 1,001 64 63

Federal Offshorea 302 341 61 66

 Pacific (California) 1 1 0 0

 Gulf of Mexico (Louisiana)a 301 340 61 66

 Gulf of Mexico (Texas) 0 0 0 0

Miscellaneousb 0 9 0 0

U.S. Total 8,557 9,809 714 745

a

 Includes Federal offshore Alabama. 

b

 Includes Arizona, Illinois, Indiana, Maryland, Missouri, Nebraska, Nevada, New York, Ohio, 

Oregon, South Dakota, Tennessee, and Virginia.

Note: The production estimates in this table are based on data reported on Form EIA-23, 

"Annual Survey of Domestic Oil and Gas Reserves" and Form EIA-64A, "Annual Report of the 

Origin of Natural Gas Liquids Production." They may differ from the official EIA production

data for 2010 natural gas plant liquids contained in the Petroleum Supply Annual 2010, 

DOE/EIA-0340(10) and the Natural Gas Annual 2010, DOE/EIA-0131(10). 

EIA Natural Gas Data

Source: U.S. Energy Information Administration, Form EIA-64A and Form EIA-23
August 2012

U.S. Energy Information Administration | U.S. Crude Oil, Natural Gas, and Natural Gas Liquids Proved Reserves, 2010 33

Table 18. Reported proved nonproducing reserves of crude oil, lease condensate, nonassociated gas, 

associated dissolved gas, and total gas (wet after lease separation) 2010a

Lease Nonassociated Associated Total

Crude Oil Condensate Gas Dissolved Gas Gas

State and Subdivision (Million bbls) (Million bbls) (Bcf) (Bcf) (Bcf)

Alaska 622 0 231 15 246

Lower 48 States 6,358 694 104,109 9,084 113,193

Alabama 0 0 162 0 162

Arkansas 1 0 7,273 1 7,274

California 522 0 254 187 441

 Coastal Region Onshore 199 0 1 34 35

 Los Angeles Basin Onshore 66 0 0 21 21

 San Joaquin Basin Onshore 210 0 253 106 359

 State Offshore 47 0 0 26 26

Colorado 180 41 6,768 759 7,527

Florida 2 0 0 0 0

Kansas 2 0 235 1 236

Kentucky 0 0 106 0 106

Louisiana 183 29 19,037 289 19,326

 North 45 6 17,635 12 17,647

 South Onshore 126 19 1,225 245 1,470

 State Offshore 12 4 177 32 209

Michigan 0 4 311 3 314

Mississippi 94 0 207 0 207

Montana 74 0 91 55 146

New Mexico 180 17 3,043 557 3,600

 East 180 16 664 552 1,216

 West 0 1 2,379 5 2,384

New York 0 0 15 0 15

North Dakota 969 42 20 900 920

Ohio 1 0 14 5 19

Oklahoma 143 66 9,856 432 10,288

Pennsylvania 0 3 5,472 0 5,472

Texas 1,883 274 32,605 3,585 36,190

 RRC District 1 144 28 1,545 180 1,725

 RRC District 2 Onshore 53 22 810 76 886

 RRC District 3 Onshore 37 15 739 140 879

 RRC District 4 Onshore 80 43 3,147 24 3,171

 RRC District 5 0 0 9,340 0 9,340

 RRC District 6 11 34 6,977 113 7,090

 RRC District 7B 8 1 890 7 897

 RRC District 7C 286 13 789 870 1,659

 RRC District 8 790 44 1,157 1,361 2,518

 RRC District 8A 418 11 1 368 369

 RRC District 9 21 8 4,043 231 4,274

 RRC District 10 35 55 3,138 215 3,353

 State Offshore 0 0 29 0 29

Utah 257 40 3,125 351 3,476

Virginia 0 0 67 0 67

West Virginia 0 1 924 2 926

Wyoming 152 86 11,593 35 11,628

Federal Offshore b 1,710 91 2,869 1,922 4,791

 Pacific (California) 13 2 0 35 35

 Gulf of Mexico (Louisiana) b 1,595 60 2,367 1,515 3,882

 Gulf of Mexico (Texas) 102 29 502 372 874

Miscellaneous c 5 0 62 0 62

U.S. Total 6,980 694 104,340 9,099 113,439

a

 Includes only those operators who produced during the report year 400,000 barrels of crude oil or 2 billion cubic feet

 of wet natural gas, or more (Category I and Category II operators).

b

 Includes Federal offshore Alabama.

c Includes Arizona, Illinois, Indiana, Maryland, Missouri, Nebraska, Nevada, Oregon, South Dakota and Tennessee.

Source: U.S. Energy Information Administration, Form EIA-23