EIA: US proved oil reserves down in 2003

Oct. 25, 2004
US proved reserves of crude oil fell 3.5% on the year to 21.89 billion bbl in 2003, the US Energy Information Administration reported.

US proved reserves of crude oil fell 3.5% on the year to 21.89 billion bbl in 2003, the US Energy Information Administration reported. It was the first decline in 5 years.

Dry natural gas reserves were 1.1% higher in 2003 at 189 tcf—he fifth straight year of increase. Gas reserves have increased in 9 of the past 10 years.

Coalbed methane reserves increased 1% to 18.7 tcf and accounted for 10% of US dry gas proved reserves. CBM production fell less than 1% to 1.6 tcf in 2003 and accounted for 8% of US dry gas production, EIA said.

Fourteen states produced CBM in 2003. The largest are Colorado, 488 bcf/year; New Mexico, 451 bcf/year; and Wyoming, 344 bcf/year.

Overall US gas production was up slightly at 19.425 tcf as production increases in the Rocky Mountain states and Texas offset declines in the Gulf of Mexico and New Mexico.

Reserves changes

Operators added oil reserves during 2003 equal to 1.232 billion bbl, or 58% of oil production, EIA said.

This figure is 16% higher than the prior 10-year average and 30% more than 2002's discoveries of 946 million bbl.

The majority of crude oil discoveries came in the Gulf of Mexico federal offshore. The Alsaka North Slope had no significant impact in 2003.

Discoveries of dry gas totaled 19.3 tcf in 2003, or 36% more than the prior 10-year average and 8% more than in 2002. The majority were from extensions of existing conventional and nonconventional gas fields.

Significant gas reserves were added in the Powder River basin (CBM) and the Green River basin (deep and tight sands) in Wyoming and in Wattenberg field (tight sand) and the San Juan basin (CBM) in Colorado and New Mexico.

Significant reserves were also added in Newark East field (Barnett shale) in Texas, the country's sixth largest gas field.

Crude oil reserves in the gulf off Texas, Louisiana, and Alabama in more than 200 m of water were 3.6 billion bbl, up 7.5% on the year. Natural gas reserves off Texas, Louisiana, and Alabama in more than 200 m of water were 10 tcf, down from 10.5 tcf in 2002.

Other results

EIA pointed out that 2003 exploratory and developmental oil well completions were up 4% from 2002 and exploratory and developmental gas well completions were up 22% from 2002.

The annual average domestic first purchase price for crude oil increased 22% from the 2002 level to $27.56/bbl, and natural gas prices at the wellhead were up 69% in 2003 to an average of $4.98/Mcf.

New field discoveries accounted for 705 million bbl of crude oil reserves additions, of which 702 million bbl were in the gulf federal offshore. This was more than double the new field discoveries of 2002 and 84% more than the prior 10-year average. New reservoir discoveries in existing fields amounted to 101 million bbl, 34% less than in 2002 and 43% less than the prior 10-year average.

New field gas discoveries were 1.222 tcf, 8% less than the volume discovered in 2002 and 33% less than the prior 10-year average. New reservoir discoveries in existing fields were 1.61 tcf, down 5% from 2002 and 34% less than the prior 10-year average.

Besides the main three states, operators reported CBM production and reserves in Alabama, Arkansas, Indiana, Kansas, Montana, Ohio, Oklahoma, Pennsylvania, Utah, Virginia, and West Virginia.

Natural gas liquids proved reserves declined 7% in 2003 to 7.459 billion bbl. EIA said this resulted from changes in the relative economics of natural gas and NGL and in the liquids content of the gas production. Included in NGL reserves are the sum of natural gas plant liquids and lease condensate.