USGS Revises Alaska's O&G Estimates Downward
The U.S. Geological Survey (USGS) has revised its estimate for conventional, undiscovered oil and conventional, undiscovered non-associated natural gas reserves both onshore and offshore Alaska to 896 million barrels and 53 Tcf respectively.
This estimate is significantly lower than USGS' estimated in 2002, when USGS estimated Alaska's undiscovered oil reserves at 10.6 billion barrels. USGS' new assessment also finds Alaska's conventional, undiscovered non-associated gas reserves to be 8 Tcf less gas than the 2002 USGS estimate of 61 Tcf.
USGS attributed the change to the incorporation of new data from 3-D seismic surveys, Federal Lease sales administrated by the Bureau of Land Management and the drilling of more than 30 exploration wells, which reveal the presence of more gas versus oil in the National Petroleum Reserve of Alaska (NPRA).
Many of the newly drilled wells show an abrupt transition from oil to gas just 15 to 20 miles west of the giant Alpine field, located outside the northeastern boundary of the NPRA.
"These new findings underscore the challenge of predicting whether oil or gas will be found in frontier areas," said USGS Director Dr. Marcia McNutt. "It is important to re-evaluate the petroleum potential of an area as new data becomes available."