"This acquisition will allow Imperial to diversify its strong resource base in Canada with an attractive liquids-rich natural gas play," said Bruce March, Imperial's chairman and CEO.
"We continue to leverage our strong balance sheet and solid financial position to grow the company through strategic resource capture in key opportunity areas."
The Celtic (TSX:CLT) acquisition — which will see both companies nab nearly 263,000 net hectares in promising B.C. and Alberta shales — is a "good complement" to land Imperial already has in northeastern British Columbia's Horn River Basin, said company spokesman Pius Rolheiser.
Unlike in the Horn River, much of Celtic's land is rich in natural gas liquids, which fetch a much higher price than ordinary dry gas.
Separately, Imperial and ExxonMobil have discussed building a liquefied natural gas export facility on Canada's West Coast to enable the fuel to reach more lucrative markets.
"We're still in the relatively early stages of that assessment," said Rolheiser.
Several companies — including Encana and Shell — have multibillion-dollar plans in the works to chill natural gas into a liquid state, making it easier to transport to Asian markets, where the price is several times higher than in North America.
Malaysia's Petronas, which is trying to win federal approval to acquire natural gas producer Progress Energy Resources Corp., also aims to build an LNG terminal in Prince Rupert.
ExxonMobil announced its $3.1-billion acquisition for Celtic more than a month ago, and at the time said Imperial (TSX:IMO), of which it owns about 70 per cent, would have the opportunity to become a 50 per cent owner.
The ExxonMobil transaction is awaiting approval from both shareholders and Canadian regulatory authorities. Imperial's participation will occur right after the deal closes.
ExxonMobil (NYSE:XOM) made a big move into natural gas in late 2009 when it announced an eye-popping US$41-billion acquisition of U.S. natural gas giant XTO.
"This new venture represents a significant opportunity to leverage ExxonMobil's expertise in shale gas development and add value for Imperial shareholders," said March.
ExxonMobil and other energy supermajors are chasing after reserve growth, said John Stephenson, portfolio manager at First Asset Investment Management.
"The majors in general, whether you're talking about Exxon or BP or Royal Dutch Shell, have really struggled over the last decade or so to find promising new basins to go and exploit," he said.
"The bigger guys are struggling to find the growth to turn the needle."
The Celtic deal will see the companies gain control of about 221,000 hectares in the Montney formation in B.C. and Alberta and 42,000 hectares in the emerging Duvernay shale in Alberta.
Current production on that land is 72 million cubic feet per day of natural gas and 4,000 barrels per day of condensate and natural gas liquids.
The assets were estimated by Celtic as of Dec. 31, 2011, to include 128 million oil equivalent barrels of proved plus probable reserves, of which 24 per cent are condensate and natural gas liquids and 76 per cent natural gas.
Imperial Oil is one of Canada's largest corporations and a major producer of crude oil and natural gas. It is also Canada's largest petroleum refiner, a key petrochemical producer and a leading marketer with coast-to-coast supply and retail service station networks.
Imperial shares rose 47 cents Wednesday to close at $42.98 on the Toronto Stock Exchange. Celtic shares closed up three cents to $26.03.