UPDATE 6-Kosmos Energy shares rise 1.3 pct in NYSE debut

* Shares close at $18.24, up 1.3 pct from IPO price of $18

* IPO sold more shares than planned at top of range

* Has stake in recently discovered oil field in Ghana

* Begins trading on NYSE under symbol "KOS"

* Citi, Barclays, Credit Suisse led underwriters (Adds oil price)

By Alina Selyukh

NEW YORK, May 11 (Reuters) - Shares of Kosmos Energy Ltd (KOS.N) rose in their debut on Wednesday as investors grabbed a piece of its massive oil field off West African coast where oil production is expected to peak this year.

The shares finished their first day of trading at $18.24, or 1.3 percent above the IPO price, on the New York Stock Exchange. This valued Kosmos at nearly $7 billion despite its lack of profits but was in line with analysts' expectations based on its oil reserves.

Kosmos, which was backed by private equity firms Warburg Pincus [WP.UL] and Blackstone Group (BX.N), raised $594 million in its IPO on Tuesday, selling more shares than expected at the top of a proposed price range.

Kosmos has caught the attention of potential buyers eager to obtain its assets in Ghana, where Kosmos made one of the world's largest recent oil discoveries in 2007.

"This area has been very hot for a while," said Fadel Gheit, analyst with Oppenheimer & Co. "These guys were there before anybody discovered West Africa."

Kosmos has a 23.49 percent stake in the Jubilee oil field, off the coast of Ghana, operated by Britain's Tullow Oil Plc (TLW.L) and holding around 1.6 billion barrels of light crude. Kosmos expects gross oil production from Jubilee to reach its design capacity of 120,000 barrels per day in the middle of this year.

The first agreement to surface was what sources said would be a $4 billion sale to Exxon Mobil Corp (XOM.N). But as reports came out about resistance from Ghana National Petroleum Corp (GNPC), Exxon called off the deal. [ID:nSGE67H089]

GNPC later made its own $5 billion offer, jointly with China's CNOOC (0883.HK), but Kosmos declined it. [ID:nSGE6A00JR]

A senior Kosmos executive then told Reuters in November that the company might opt for a private and later public placement instead of a sale to raise more cash for further development of its assets in Ghana. [ID:nWEA6489]

Dallas-based Kosmos has five exploration licenses in Ghana, Cameroon and Morocco and operates under three of them, it said in a filing with U.S. financial regulators.

Kosmos only has proved reserves of 56 million barrels of oil through its Jubilee stake, but analysts at Houston-based investment bank Tudor Pickering Holt put its per-share valuation at $17.20 to $19.40, based on "proven, probable and possible" reserves and oil prices of $90 to $100 per barrel.

U.S. crude oil prices tumbled on Wednesday by more than 5 percent, falling below $100 a barrel, after data showed increases in crude and gasoline inventories and signs that China's economy is cooling. For more details [ID:nN11236165]

The company is operating in the red, and its losses have grown in the past five years, reaching $323 million in 2010.

Kosmos plans to spend the IPO proceeds on development and exploration in Ghana and Cameroon as well as new ventures to get more licenses, its filing said. It also plans to pay GNPC $15 million to "resolve our past disputes," it added.

In its IPO, Kosmos sold 33 million shares at $18 each after planning to sell 30 million in an expected range of $16-$18.

None of the company's shareholders sold their stakes in the IPO. The offering reduced private equity shareholders' stake in Kosmos to 76 percent from 83 percent: Warburg Pincus has 42 percent and Blackstone has 34 percent.

Kosmos Chief Executive Brian Maxted previously led the oil exploration team at Triton Energy, building on his experience in hunting for oil in the North Sea, Egypt, Canada, Norway and Colombia with BP Plc (BP.L) (BP.N).

Citigroup, Barclays Capital and Credit Suisse led underwriters on the IPO. (Additional reporting by Braden Reddall in San Francisco and Matt Daily and Megan Davies in New York; editing by Dave Zimmerman, John Wallace and Steve Orlofsky)