FACTBOX-Key shale gas deals since 2009

May 11 (Reuters) - British gas producer BG Group (BG.L) has agreed to pay $950 million for a 50 percent stake in shale gas assets in Appalachia from EXCO Resources (XCO.N), the latest in a string of such deals between the firms. [ID:nLDE6490DB]

Below are major shale gas sector acquisitions since 2009:

MARCH 2009:

-- Independent Canadian oil exploration firm TriStar Oil & Gas TOG.TO and Crescent Point Energy Trust agreed to buy Talisman Energy Inc's lands in the prolific Bakken shale region of Saskatchewan and Montana for C$720 million ($567 million).

MAY 2009:

-- Talon Oil & Gas LLC bought 60 percent of Denbury Resources Inc's (DNR.N) natural gas assets for $270 million. [ID:nBNG368319]

-- Independent oil and gas company Quicksilver Resources Inc (KWK.N) agreed a joint venture with Italian energy giant Eni (ENI.MI) to develop its Barnett shale properties in Texas. [ID:nBNG161361]

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

JUNE 2009:

-- British gas producer BG Group paid Dallas-based Exco Resources Inc (XCO.N) $1.3 billion for an interest in shale gas resources in Texas and Louisiana. [ID:nLU618520]

The companies said each would own 50 percent of a venture to which EXCO is contributing 120,000 acres of land in the Haynesville shale gas area and associated gas infrastructure.

NOVEMBER 2009:

-- Denbury said it would buy Encore Acquisition Co EAC.N for $3.2 billion, creating a company with 426 million barrels of oil equivalent in proved reserves. [ID:nN02456478]

The acquisition would allow Denbury to leverage its enhanced-oil-recovery business into Encore's properties in Wyoming, Montana, and North Dakota, and would give it a large stake in the Bakken shale on the U.S.-Canada border.

DECEMBER 2009:

-- Ultra Petroleum Corp (UPL.N) said it would pay about $400 million to an unnamed private company to buy 80,000 net acres in the burgeoning U.S. Marcellus Shale region, giving it about 250,000 net acres and a potential for 1,800 net drilling sites. [ID:nSGE5BK0EU]

FEBRUARY 2010:

-- Canada's Progress Energy Resources Corp (PRQ.TO) agreed to buy certain northeast British Columbia Foothills assets for about C$390 million ($366.2 million) from Suncor Energy (SU.TO). [ID:nSGE6180KX] APRIL 2010:

-- British gas producer BG Group (BG.L) said it would pay $950 million to buy a 50 percent interest in shale gas assets in Appalachia from EXCO Resources (XCO.N).

(Writing by Carl Bagh, Bangalore Editorial Reference Unit; Editing by David Cutler and Simon Jessop)