* North Sea Buzzard oilfield restart delayed again
* Keystone pipeline seen back up at weekend
* Spanish bailout worries drag on markets (Adds details on weekly activity, CFTC report in last paragraph)
By Robert Gibbons and Matthew Robinson
NEW YORK, Oct 19 (Reuters) - Brent crude prices fell on Friday for the fourth straight session, dragged down by fresh global economic concerns and expectations a major Canadian crude oil pipeline to the United States would restart on schedule.
Concerns about the lack of progress on a Spanish bailout dampened risk appetite, helping send equities and commodity markets lower and lending support to the dollar.
Oil prices initially turned negative in early U.S. trade following news that TransCanada Corp expected to restart the 590,000-barrel-per-day Keystone pipeline to the U.S. market over the weekend despite poor weather hampering efforts.
The line was shut on Wednesday after an anomaly was detected, but analysts said that with U.S. crude oil inventories healthy, the market should be able to absorb a short-term disruption with little problem. U.S. crude stocks are nearly 11 percent above year-ago levels, according to government data.
"Because of the ample supplies of oil (in the United States), a three-day closure is not extremely bullish -- if they announce a delay that's when the market will start to get a bid in it again," said Gene McGillian, analyst at Tradition Energy in Stamford, Connecticut.
Further pressure on prices came from a report showing U.S. home resales retreated in September from a two-year high.
Oil markets have been balancing the struggling economy and weak demand against supply problems in the North Sea, which have helped lift Brent crude's premium to U.S. oil to $20 a barrel.
Crude prices received an early lift on news that there was another delay in the restart of the North Sea Buzzard oilfield, which is now expected to restart on Oct. 23 after a maintenance shutdown.
Brent December crude fell $2.28 to settle at $110.14 a barrel. The international benchmark traded as high as $113.27, just below the 50-day moving average of $113.33, before dipping as low as $110.05.
U.S. front-month November crude lost $2.05 to settle at $90.05 a barrel, after finding resistance at $93 a barrel area and testing support under $90 near the 100-day moving average.
Brent volumes were light, about 20 percent below its 30-day average, while U.S. trading activity was closer to normal levels.
Gasoline and heating oil futures also fell, off 1.6 and 1.4 percent, respectively, finding some support relative to crude prices due to concerns about supplies.
For the week, Brent lost $4.48, or 3.9 percent, while U.S. crude gave up $1.81, or 1.9 percent. Money managers cut net long positions by nearly 3,000 contracts to just over 193,000 contracts, in the week to Oct. 16, according to data from the U.S. Commodity Futures Trading Commission. (Additional reporting by Claire Milhench in London and Florence Tan in Singapore; Editing by Chizu Nomiyama, Marguerita Choy and Kenneth Barry)