Occidental Petroleum Corp. on Friday made two deals valued at $3.2 billion that give it entry into the Eagle Ford Shale and boost its land holdings in the Bakken Shale.

In one transaction, Occidental agreed to pay Royal Dutch Shell plc $1.8 billion for a piece of its 100%-operated leasehold in the Eagle Ford in South Texas. The properties now produce 200 MMcfe/d, Occidental said.

Occidental also agreed to pay $1.4 billion to an undisclosed private seller for 180,000 net acres in the Bakken Shale’s Three Forks Formation of North Dakota. The assets currently produce about 5,500 boe/d, and the net risked reserve exposure is estimated at more than 250 million boe.

The purchases, combined with acquisitions earlier this year, will “more than replace the production” from the $2.45 billion sale of the company’s Argentina unit to China Petrochemical Corp., said Occidental CEO Ray Irani. The sale to the Chinese refiner, also known as Sinopec, was announced on Friday as well.

For Shell, selling the Eagle Ford assets was part of a portfolio restructuring plan.

“We are concentrating our investment on the most promising growth opportunities and that means taking a hard look at existing assets like our fields in South Texas, where we have been active for more than 50 years,” said Shell’s Marvin Odum, who directs Upstream Americas. “This sale helps move us towards our goal of divesting $7-8 billion in assets worldwide in 2010 and 2011 and rationalizing our North American portfolio following on from recent acquisitions there.”

The Eagle Ford fields, predominately “mature tight gas,” include all of Shell’s gas-producing properties and related assets in South Texas, where the company drilled its first well in 1953.

The fields being divested by Shell include McAllen Ranch, Javelina, McAllen Pharr, Slick Ranch and La Copita/North Incan.

However, Shell said it is not letting go of separate Eagle Ford property that it acquired through its $4.7 billion acquisition of East Resources Inc. earlier this year (see Daily GPI, June 1). In the East transaction, Shell gained not only a substantial leasehold in the Marcellus Shale, but 250,000 net acres of undeveloped mineral rights in the liquids-rich portion of the Eagle Ford.

Combined with its current leasehold in the Williston Basin of North Dakota, Occidental said it would have more than 200,000 net acres across the oil shale region that would produce more than 6,000 boe/d of production. Output in the Williston Basin is expected to jump “at least 30,000 boe/d” in the next five years.

“With these new acquisitions and without Argentina in our asset mix, achieving both our short-term and long-term average annual production growth outlook of 5-8% will be more certain and will generate higher returns,” said Irani. “We expect that each of these new acquisitions together with future drilling, potential exploration and consolidation opportunities in these areas, over time, will grow to over 50,000 boe/d.”