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US oil reserves up, Alaska’s down EIA says shale oil development driving major increase in Lower 48 reserves while Alaska’s conventional production declines Alan Bailey Petroleum News
With a rise of 9 percent to 36.5 billion barrels, U.S. oil and condensate reserves increased in 2013 for the fifth consecutive year, EIA, or the Energy Information Administration, reported Dec. 4. But Alaska bucked the trend, having seen a reserves decline of 454 million barrels, a drop of 14 percent, the largest decline of any of the oil producing states. The 36.5 billion barrel figure for the United States as a whole represents the first time since 1975 that reserves have exceeded 36 billion barrels, the agency said.
Reserves are volumes of oil known to exist through drilling and believed to be technically and economically feasible to develop. Reserve volumes, as distinct from estimates of possible undeveloped resources, vary, depending on levels of exploration and development drilling; the maturity of operating oil fields; and the price of oil.
EIA attributes much of the reserves increase to new shale oil development, particularly in North Dakota and also in Texas, with the majority of the growth coming from the expansion of existing plays rather than from new discoveries. The agency said that the Alaska decline resulted from reduced well performance in large, existing oil fields.
Thanks to development in the Bakken/Three Forks formation in the Williston basin, North Dakota saw the largest reserves increase of any state, with the reserves growing by 1.9 billion barrels or 51 percent to a total of 5.7 billion barrels. The state now has more reserves than the Gulf of Mexico outer continental shelf, EIA said. However, Texas has by far the most reserves, with the reserves volume there increasing from 11.1 billion to 12 billion barrels, or 8 percent, in 2013.
In 2013 Alaska had oil and condensate reserves of 2.9 billion barrels, EIA reported.
Gas reserves U.S. natural gas reserves increased from 323 trillion to 354 trillion cubic feet between 2012 and 2013, with these reserves increasing in each of the top five gas producing states: Texas, Pennsylvania, Wyoming, Oklahoma and Colorado, EIA said. Pennsylvania saw the biggest increase, thank to extensions to fields in the Marcellus shale. Texas and Oklahoma also saw expansions in shale gas plays, while reserves increases in Wyoming and Colorado came from large conventional gas fields. As with oil, gas reserves growth came mainly from the expansion of existing plays rather than from new discoveries.
The increase in natural gas reserves in 2013 did not fully offset a reserves decline in 2012, presumably because producers remained cautious about drilling new prospects in the wake of low gas prices.
EIA reported that Alaska has natural gas reserves of 7.4 trillion cubic feet, a figure that does not appear to include much of the gas known to exist in the Prudhoe Bay and Point Thomson fields - in the absence of an export gas line most of the gas in these fields is currently stranded from market and cannot, therefore, be economically produced. In fact, Alaska saw a downwards revision of 2.3 trillion cubic feet in gas reserves, largely as a consequence of a drop in proved reserves of gas associated with oil production, as well performance declined in some fields, EIA said.
The reserves data that EIA collated presumably related to oil and gas prices in 2013, and did not therefore reflect the sharp downward trend in the recent price of oil.
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