US STOCKS-Futures flat on global concerns, Halliburton falls

* Trading volume low as quarter nears end

* Halliburton down after comments, Lennar shares rally

* Case-Shiller home prices, consumer confidence on tap

* Futures up: Dow 23 pts, S&P 1.9 pts, Nasdaq 6 pts

* For up-to-the-minute market news see [STXNEWS/US] (Adds comment, corporate results)

By Ryan Vlastelica

NEW YORK, March 29 (Reuters) - U.S. stock index futures were flat on Tuesday near the quarter's end as investors took a wait-and-see stance, unsure about the impact of global crises.

In one sign of the spillover from overseas events, oilfield-services company Halliburton Co said its quarterly earnings were hurt in part by turmoil in oil-producing regions.

The S&P 500 index is up 4.2 percent in the quarter, and in the absence of further clarity on such issues as Japan's nuclear power problems and the civil unrest in the Middle East and North Africa, many investors are choosing not to risk their gains. The trading volume in Monday's session was the lowest of the year.

"Despite the significant events in the Middle East and Japan, the market has help up very well, so many portfolio managers are staying pat as the quarter ends," said Oliver Pursche, president at Gary Goldberg Financial Services in Suffern, New York. "Until we get a better handle on those issues, there's no overwhelming reason to become more invested."

Late Monday, Halliburton said it would cut its first-quarter earnings because of the unrest in the Middle East and North Africa and weather-related events in North America and Australia. The stock slid 1 percent to $47.40 in light premarket trading. For details, see [ID:nN2852973]

Pursche said that while other oil-related stocks could face similar issues, he didn't expect the overseas events to impact results in the upcoming earnings season.

Lennar Corp rose 2.3 percent to $20.20 before the bell after the homebuilder swung to profit in the first quarter. [ID:nL3E7ET1SX]

Dow component Home Depot Inc late Monday said it would buy back $1 billion of outstanding shares through an accelerated stock buyback program with Barclays. [ID:nN28219743] Its shares rose 1.6 percent to $37.24 in light premarket trading.

S&P 500 futures rose 1.9 points but 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 added 23 points and Nasdaq 100 futures rose 6 points.

Spicemaker McCormick & Co reported a first-quarter profit that beat expectations, while Apollo Group fell 7.9 percent to $39.02 in premarket trading after the education company said new enrollment fell 45 percent in second quarter. [ID:nL3E7ET1XW] [ID:nL3E7ET1V1]

Economic indicators include January Case-Shiller data, due at 9 a.m. [1300 GMT] and March consumer confidence, which is seen falling from the prior month.

Wal-Mart Stores will urge the U.S. Supreme Court on Tuesday to reject a case brought on behalf of female employees who allege the retailer gave women less pay and fewer promotions in the largest, class-action sex-discrimination lawsuit ever. [ID:nN28284791]

Goldman Sachs downgraded property and casualty insurance company Travelers Cos Inc . [ID:nL3E7ET1JZ]

On Monday, U.S. stocks fell, with consumer shares hurt after hotel operator Marriott International . (Editing by Kenneth Barry)