ExxonMobil said it will more than double its Permian Basin resource to six billion barrels.
The move will be made through the acquisition of firms owned by the Bass family of Texas.
They have an estimated resource of 3.4 billion barrels of oil equivalent in New Mexico’s Delaware Basin.
The company will make an upfront payment of $5.6billion in shares as well as a series of additional contingent cash payments totaling up to $1billion.
It will be paid starting from 2020 and ending no later than 2032 with the development of the resource.
Chief executive Darren Woods said the properties are a major addition the firm’s unconventional liquids portfolio.
He said:“This acquisition strengthens ExxonMobil’s significant presence in the dominant US growth area for onshore oil production.
“This investment gives us an exceptional Delaware Basin position in a proven multi-stacked play that can generate attractive returns in a low-price environment.
“The highly-contiguous position will provide significant cost advantages in developing 3.4 billion barrels of resource, of which 75 percent is liquids. By utilizing ExxonMobil’s technological strength coupled with its unconventional development capabilities we can drill the longest lateral wells in the Permian Basin, reducing development costs and increasing reserve capture.”