* Libyan violence pressures global markets
* Oil prices hit 2-1/2 yr high
* S&P/Case-Shiller, consumer confidence data on tap
* Futures off: S&P 15.7 pts, Dow 85 pts, Nasdaq 31 pts
* For up-to-the-minute market news see [
] (Adds byline, quote)By Angela Moon
NEW YORK, Feb 22 (Reuters) - U.S. stock index futures tumbled on Tuesday as a revolt in Libya drove investors away from risky assets and prompted a spike in crude oil prices.
Libyan leader Muammar Gaddafi used tanks, helicopters and warplanes to quell a growing revolt as the veteran leader scoffed at reports he was fleeing after four decades in power. For details, see [
]Crude oil futures <CLc1> hit a 2-1/2 year high on concerns the Libyan violence could cut more of the OPEC member's output, and that a similar story could play out in other top oil producers in North Africa and the Middle East.
Global stock markets were pressured as investors feared civil unrest in the Middle East and North Africa would keep oil prices high, driving up inflation, cutting into corporate profits and crimping economic growth.
S&P 500 futures <SPc1> fell 15.7 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures <DJc1> slid 85 points, and Nasdaq 100 futures <NDc1> tumbled 31 points.
Elsewhere in the Middle East, two Iranian naval ships entered the Suez Canal, a canal official said, heading toward the Mediterranean, a move certain to anger Israel. [
]"These are cases of real concerns, real jitters. People are avoiding stocks based on risk aversion and flocking to more traditionally safe-haven investments such as bonds and gold," said Peter Cardillo, chief market economist at Avalon Partners in New York.
In Europe, the pan-European FTSEurofirst 300 <
> index of top shares fell 0.6 percent, extending the previous session's losses on the Libyan worries.Shares of Wal-Mart Stores Inc <WMT.N> fell 1.5 percent to $54.55 in premarket trade after the world's largest retailer posted its seventh straight drop in key U.S. sales during the chain's most important quarter. [
]Home Depot Inc <HD.N>, the world's largest home improvement chain, reported higher-than-expected quarterly profit as shoppers began long-delayed home projects in a slowly recovering U.S. economy. Its shares rose 2.3 percent to $39.37 premarket. [
]Hewlett-Packard Co <HPQ.N>, the world's largest technology company by revenue, is seen reporting strong demand for networking equipment, servers and storage when it reports results later Tuesday, but relatively lackluster sales of personal computers. [
]Investors will also focus on the S&P/Case-Shiller December report on house prices, due at 9 a.m. EST (1400 GMT). The data is expected to show U.S. single-family home prices fell for a sixth straight month in December, according to a Reuters survey of economists.
U.S. consumer confidence data for February is set for 10 a.m. EST (1500 GMT). Economists look for a reading of 65.0, compared with 65.6 previously, according to a Reuters survey.
BHP Billiton Plc <BLT.L> is buying Arkansas shale gas reserves from Chesapeake Energy Corp <CHK.N> for $4.75 billion in a big bet on the world's biggest gas market. Chesapeake Energy shares rose 5.6 percent to $32.12. [
]U.S. markets were closed on Monday for the U.S. Presidents Day holiday, but on Friday stocks pushed higher for a third week despite growing signals of an overheating market. (Reporting by Angela Moon; editing by Jeffrey Benkoe)