The USGS study of Denmark is its first-ever assessment of the shale natural gas potential there. The results of the study were delivered Tuesday to the Geological Survey of Denmark and Greenland, which provided data to the USGS.
The Alum shale area consists of an offshore and onshore section, with the latter accounting for the bulk of the estimated reserves. USGS said it doesn't believe the area contains significant quantities of oil.
Shale oil and natural gas extraction in North America has redefined the dynamics of the international energy market in part because the U.S. and Canadian economies are relying less on foreign energy reserves.
USGS Acting Director Suzette Kimball said the Alum shale may be a potential reserve basin for Denmark though exploitation may be difficult.
"The complicated geology in Denmark and the difficulty involved in assessing it really demonstrates how important it is to have a robust geologic model underpinning all of our assessments," she said in a statement Tuesday.
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