Caelus Energy LLC agreed to buy the Alaska subsidiary of Pioneer Natural Resources Co. (NYSE: PXD) for $550 million in cash.

The sale of Pioneer Natural Resources Alaska Inc. is expected to close by the end of 2013.

Proceeds from the deal will be put toward Pioneer’s core business, the Spraberry-Wolfcamp oil asset located within the Permian Basin in Texas, according to Pioneer chief executive Scott Sheffield in a statement. The Irving, Texas-based company plans to increase the rig count in the area, which Pioneer expects will yield more than 3 billion barrels of oil equivalent.

Caelus is headquartered in Dallas.

This is the first deal for Pioneer since it announced plans to acquire drilling company Pioneer Southwest Energy Partners in August.

Energy industry