Financial distress is soon expected to trigger long-awaited sales of oil and gas properties in North Dakota's Bakken and Texas' Eagle Ford basin, the chief executive of Anadarko Petroleum Corp said on Nov. 10.

A prolonged downturn in crude oil prices has generated lots of chatter that companies laboring under heavy debt that operate shale fields with high break-even costs will have to sell assets to generate much-needed cash.

As low crude oil prices linger for more than a year, distress is intensifying and may finally bring some of those properties to market.

"We've not really seen good distressed assets make their way into the market," CEO Al Walker told investors at Bank of America Merrill Lynch's Global Energy Conference. "For companies that have positions in the Bakken, they probably will start to see that sooner than others."

Distressed Eagle Ford asset sales are also likely in the near-term, said the CEO of the Houston-based company that has shale wells in Eagle Ford.

Still, Anadarko is most interested in adding assets in areas where it already had access to pipelines and other infrastructure needed to bring oil to gas to market like Colorado's DJ Basin and West Texas' Delaware Basin, said Walker.

Pioneer Natural Resources Co CEO Scott Sheffield said at another conference on Tuesday that he believed the Permian Basin "is the only place long-term to grow oil in this country."

Permian operators have dozens of layers of oil-bearing rock to drill, while wells in the Bakken and Eagle Ford have big decline rates, said Sheffield.

He said he would not be surprised if Pioneer's Eagle Ford acreage was not part of the company in five years, while the Eagle Ford contributes 20 percent to their production.