Benchmark crude slid $1.95 Wednesday to finish the day at $89.90 per barrel.
The decline came on the heels of several weeks of slipping oil, sparked by a plethora of less than stellar economic reports. The concerning data mostly involved Europe's ongoing sovereign debt saga.
Oil gained 0.5% in early afternoon New York trading Thursday, but the reasons for the rally were unclear.
"You don't know if this is just a short-covering rally or the start of a more significant rally," Andy Lebow, an oil analyst with Jefferies, told The Wall Street Journal. Lebow said that progress in the talks between Iran and Western powers about Tehran's nuclear ambitions could have spurred Thursday's price reversal.
If the gain isn't maintained, however, prices could head closer to $85 a barrel.