"The Gadhafi regime has fallen and no one is interested," said Commerzbank analysts. "The market apparently doesn't quite want to believe in a quick return of Libya's oil production." But "we believe the market is underestimating this scenario, both in terms of time scale and production volume," the analysts warned. The analysts say that oil companies are already on their way back to Libya to prepare for a resumption of production. Natural gas for September delivery was falling 4 cents to 3.957 per million British thermal units on expectations of a big stockpile injection to be reported on Thursday. Industry analysts surveyed by Platts expect the Department of Energy to report a natural gas inventory build of 72 billion cubic feet to 75 billion cubic feet for the week ended Friday. Platts said a natural gas build within analysts' expectations would be above both the year ago and five-year average injections. The Department of Energy releases its weekly natural gas inventory report at 10:30 am ET Thursday. "Storage tomorrow could be a whopper vs. last year's 38 Bcf, hence natty is struggling to hold its head above $4, despite immediate factors being conducive for a rally," said Summit Energy analyst Matt Smith. Natural gas prices had popped 10.4 cents Tuesday in reaction to the earthquake that struck the East Coast of the U.S. "Traders bought natural gas futures as a hedge against the possibility of nuclear plant closures after yesterday's 5.8 earthquake," Cameron Hanover analysts explained. Energy stocks were trading mixed. Royal Dutch Shell was falling 1% to $64.79; Petrobras Argentina ( PZE) was adding 1.3% to $16.59; Suncor Energy ( SU) was rising 0.7% to $30.66; Imperial Oil Limited ( IMO) was gaining 2% to $40.71; Southern Union Company ( SUG) was up 0.1% to $41.64; Atlas Pipeline Partners ( APL) was tumbling 1.4% to $27.57; and Copano Energy ( CPNO) was falling 0.9% to $30.31. -- Written by Andrea Tse in New York. >To contact the writer of this article, click here: Andrea Tse.