UPDATE 2-Quicksilver in JV with Italy's Eni

* Eni to buy 27.5 pct stake in Alliance leasehold interests

* Companies to exchange technical data

* Quicksilver shares jump 16 pct, Eni up 4 pct (Recasts; adds details, analyst comments, share movement)

May 18 (Reuters) - Independent oil and gas company Quicksilver Resources Inc (KWK.N) said it entered into a joint venture agreement with Italian energy giant Eni (ENI.MI) (E.N) to develop its properties in Texas' Barnett shale.

Shares of Fort Worth, Texas-based Quicksilver jumped 16 percent to $9.92, while Eni shares were up about 4 percent at $45.30 in midday trade on the New York Stock Exchange.

As part of the agreement, Eni will buy a 27.5 percent stake in Quicksilver's Alliance leasehold interests in the Fort Worth basin for $280 million.

The companies will also exchange technical data, particularly in drilling and completion technologies and geophysics.

The deal, which includes the sale of 131 billion cubic feet (Bcf) of proved reserves and 96 Bcf of probable and possible resources, is expected to close by June 15, Quicksilver said.

However, the transaction does not include Quicksilver's midstream gathering infrastructure or any of its existing leasehold beyond the Alliance properties.

Quicksilver said it would use the net proceeds to repay debt.

Jefferies & Co analyst Subash Chandra said Quicksilver's joint venture with ENI helps solve the second lien loan problems, marks-to-market reserves to a higher value, and validates the Alliance acquisition made at the peak of the market.

"Retirement of the second lien will eliminate the most restrictive covenants, which we believe is in KWK's best interest," Chandra wrote in a note to clients.

Last month, Quicksilver's lenders raised the interest rates on its $1.2 billion revolving credit facility as part of an amendment that affirmed the borrowing base. [ID:nBNG446496]

Chandra said the value Quicksilver is getting for its properties is well above the value that Denbury Resources Inc (DNR.N) got for its assets and that the Denbury deal was not representative of core Barnett values.

Last week, Denbury said it will sell 60 percent of its Barnett Shale natural gas assets for $270 million and use the proceeds to repay its outstanding bank debt.[ID:nBNG368319]

Barnett shale is one of the many shale plays that have come into prominence in recent years. These shales are geological formations where oil and natural gas are trapped in layers of rock.

Record energy prices and technological advances had made retrieving hydrocarbons from the shales profitable and led many companies to take on huge amounts of debt to purchase properties in these shales. (Reporting by Hezron Selvi and Santosh Nadgir in Bangalore; Editing by Anne Pallivathuckal and Deepak Kannan)