As the energy earnings season has been turned over to the independent producers, it's becoming progressively clearer that, for the time being at least, their center of productive action lies in the various formations of the U.S. of A. That certainly is the situation with Houston-based Apache Corporation (APA 0.40%), which is working feverishly to concentrate its exploration and production activities on its home continent.

As the company shifts its focus and highgrades its assets, however, it's cranking out something less than stellar financial results for the time being. For the final quarter of 2013, Apache recorded net profit of $174 million, or $0.43 per share. That result compares with $649 million, or $1.64 a share, for the comparable quarter a year earlier. But if you back out one-time items, the per share number for the most recent period bobs up to $1.57.

The analysts who follow the company had anticipated earnings closer to $1.79 per share. But when a company is undergoing asset sales or acquisitions at a rapid clip, I tend to take external forecasts with virtual shaker of salt.

Total production for the quarter averaged 688,000 barrels of oil equivalent per day, down 14% year over year. A major culprit involved the frigid weather that continues to grip much of the U.S., including Texas, Oklahoma, and New Mexico, all states in which the company is an active producer.

Heavy sale volume
In its drive to concentrate on North American activities, Apache sold off more than $7 billion in properties during 2013, leading to fully 60% of the company's production occurring the U.S. and Canada during the fourth quarter. For the full year, as CEO Steve Farris noted on his post-release conference call, during 2013 Apache was the most active driller in the onshore U.S., "running an average of 71 rigs and completing 1,150 wells."

A significant portion of the company's U.S. success has occurred in the revitalized Permian Basin of southwest Texas and southern New Mexico. In that active venue, Apache replaced almost 325% of its production during the year, while upping its reserves by 14%. Amazingly, Permian reserves now represent more than a third of the company's global total.

Internationally, Apache operates in the dessert of Western Egypt, Australia, and the North Sea. Immediately prior to its latest earnings announcement, it said that it had agreed to sell all its assets in Argentina to that country's state-run YPF SA (YPF 4.59%). The deal, which is likely to close within the next month or so, will add about $800 million to Apache's cash coffers, and will include about 540 billion cubic feet of estimated natural gas reserves and daily production of 256 million cubic feet.

Most of the properties included in the exchange are located in Neuguen, Rio Negro, and Tierra del Fuego provinces. They represent the biggest addition to YPF's repertoire since the national oil company confiscated a 51% stake in Argentine assets from Spain's Repsol SA in 2012. Apache also is selling its assets in the hot Vaca Muerta (dead cow) shale play in the western part of the country to Pluspetrol SA for $217 million.

The Argentine asset sale is neither the first nor the largest of Apache's recent divestitures. Last summer the company raked in $3.1 billion by selling a one-third stake in its Egyptian properties to China's giant Sinopec Group.

Others concentrating in North America
And Apache also isn't the only sizable independent producer that's essentially hunkering down on its home continent. You've likely been following the immense successes being chalked up by EOG Resources (EOG 0.25%), which is adding steadily and substantially to its production in the Eagle Ford shale of South Texas, the Bakken formation in North Dakota, the Permian, and the DJ Basin of Colorado and Wyoming. A large part of EOG's success has resulted from management's ability to steadily improve its production techniques in all its plays.

As my colleague Arjun Sreekumar told you recently, while Anadarko Petroleum (ARC 0.73%) reported a sizable loss for its most recent quarter, that bit of red ink was dragged out as a result of an $850 million reserve related to a legal action tied to its Kerr-McGee unit. More importantly for the longer term, the company has been able to expand its total production largely through output increases in the Wattenberg field (located in the DJ Basin) and the Eagle Ford.

Foolish takeaway
The analysts are currently somewhat higher on EOG and Anadarko than on Apache. In the short term, I'm willing to chalk up that differential to the dust having yet to settle from the last-name producer's portfolio overhaul. Nevertheless, I'm urging Fools with a thirst for energy to keep close tabs on the independents for whom home more and more is where the production is.