Marathon Oil will sell its Wyoming assets to Merit Energy for $870 million in a deal that includes the state's most productive oil fields.

The sale announced Monday includes Marathon's properties in the Big Horn and Wind River basins.

It comes after company executives said last year they would sell non-core assets to raise money amid falling oil prices.
The purchase by Dallas-based Merit Energy will put Marathon on track to exceed its goal of $750 million to $1 billion in asset sales.

Marathon, which has had a presence in Wyoming for more than a century, has turned to shale in North Dakota and Texas in recent years.

The deal with Merit is expected to close in mid-2016.