HOUSTON, July 18 (Xinhua) -- Oil prices plunged Thursday as production in the U.S. Gulf of Mexico is expected to rise again next week with oil rigs returning to operation.

Futures prices for West Texas Intermediate Crude fell 1.48 U.S. dollars, or 2.6 percent to settle at 55.30 dollars per barrel on Thursday. The U.S. benchmark on Wednesday declined 1.5 percent, after a drop of 3 percent on Tuesday.

Futures prices for Brent crude also fell 1.94 dollars, or more than 3 percent to settle at 61.72 dollars a barrel. Earlier, they declined 1 percent on Wednesday and 3 percent on Tuesday.

"Gulf of Mexico production is beginning to restart," Tom Kool, editor of OilPrice.com, told Xinhua on Thursday. U.S. oil output dipped precipitously last week as Hurricane Barry hit the Gulf of Mexico.

Roughly 70 percent of oil production in the Gulf of Mexico, or 1.3 million barrels per day of output, was offline at the start of this working week. In addition, an estimated 1.7 billion cubic feet per day of natural gas were not produced.

Late last week, platforms were evacuated by oil workers ahead of Hurricane Barry, the U.S. Bureau of Safety and Environmental Enforcement, a division of the Interior Department, said.

The process of resuming halted production is gradual and slow. Chevron started returning staff and restoring output earlier this week for its Big Foot, Blind Faith, Genesis, Jack St. Malo, Petronius and Tahiti oil drilling platforms in the Gulf of Mexico, the company said.

Shell said it shut the production at the Auger, Salsa and Enchilada drilling sites and slowed the production at the Mars Corridor location, and was working to resume normal output as soon as it is safely feasible.

Analysts said that to restart drilling, the oil platforms first need to be inspected and assessed, and then third-party suppliers must be checked.

The hurricane-related shutdown is harming the profitability of oil platforms, analysts said, as it drives up overall costs.