Those idle leases are mostly w/o oil or nat gas. They lease a tract just to do a seismic survey, if the results are good they wait for a drilling rig to become available and drill. Most leases dont contain oil or gas. Seismic surveys have reduced dry hole drilling by maybe 50=60%.
THere are at least 1 significant oil field in Alaska that are not being produced because the Alaska pipeline has yet to be extended to that field, Pt Thompson. Alpine was waiting a few years for an extension of the Alaska pipeline, Alpine is now producing.
North American reserves are estimated to be between 10 & 20 giga barrels. Most of that is low quality thick oil in rock of low porosity, so the oil doesnt flow very easily.
http://pubs.usgs.gov/fs/fs-0028-01/fs-0028-01.htm " ANWR has 10 smaller oil fields. 95% chance of holding 3.4 bb.
http://pubs.usgs.gov/fs/2002/fs045-02/figure6.htmlNPRA has 4 oil larger fields, 95% chance of holding 5.9 bb
http://pubs.usgs.gov/fs/2002/fs045-02/Drill smart
I again digress:
"Senator Menendez"
Fact: Oil Companies Have Access to 100 Billion Barrels of Oil. Oil companies have access to 100 billion barrels of conventional oil under federal lands and waters that are not under any moratoria and are being leased or are available for leasing.
.
http://menendez.senate.gov/newsroom/record.cfm?id=299804
Interior Department has estimated 18 billion barrels of oil available off shore under a congressional ban.
http://www.doi.gov/issues/expanding_oil.html
100mb in existing leases should be produced before the 18mb found offshore in banned areas are.
Drill smart.