By Barani Krishnan
NEW YORK (Reuters) - Oil prices inched higher on Thursday in see-saw trade, tracking gains in Wall Street equities for a second straight day despite a weekly build in U.S. crude inventories that weighed on the outlook for oil.
Reprising Wednesday's volatility, crude oil futures rallied more than $2 a barrel, then retreated. Global benchmark Brent slipped into negative territory before edging up to settle modestly higher.
"Early strength and a late fade," Donald Morton, an oil trader with Fairfield, Connecticut-based Herbert J. Sims & Co., said, describing the action.
Brent's front-month contract, settled up 18 cents at $50.68 a barrel. At one point during the session it had risen above $52.
U.S. crude's front-month gained 50 cents, settling at $46.75. It went above $48 earlier.
The market staged an early rally on Wall Street, then sputtered on caution over a U.S. jobs report due on Friday that will probably influence the Federal Reserve's decision on a potential interest-rate hike. [.N]
Adding to early support for oil was the European Central Bank's pledge to keep monetary policy after weak inflation and growth forecasts.
In China, markets closed for public holidays for the rest of the week, lending calm to oil and other assets battered by last month's tumble in Chinese equities.
Oil prices remained under pressure though, from Wednesday's U.S. government data showing crude stocks swelling 4.7 million barrels in the latest week, the biggest weekly rise since April.
On Friday, the market will also watch the U.S. oil rig count for direction. The rig count has risen for six consecutive weeks so far, and any drop could bolster oil's price outlook. [RIG/U]
Oil prices have been a wild ride over the past two weeks. U.S. crude plunged to a 6-1/2-year low of $37.75 early last week, then climbed almost 28 percent over three trading sessions into Monday. It has since retraced much of that three-day gain.
Traders and analysts braced for more volatility ahead.
"Oil is technically exhausted after being whipsawed violently over the past few weeks," said Chris Jarvis, analyst at Caprock Risk Management in Frederick, Maryland.
"Bulls have little to hang their hat on and shorts have just been taken to the cleaners. Both bears and bulls have gone to their respective corners for a breather."
(Additional reporting by Libby George in London and Keith Wallis; in Singapore; editing by Susan Fenton, Andrew Hay and David Gregorio)