Chord Energy (CHRD) 8-K Oasis Petroleum Inc. Announces Financial and Operational Update and 2021 Outlook and Declares First Dividend

Exhibit 23.1

DEGOLYER AND MACNAUGHTON

5001 SPRING VALLEY ROAD

SUITE 800 EAST

DALLAS, TEXAS 75244

February 24, 2021

Oasis Petroleum Inc.

1001 Fannin Street, Suite 1500

Houston, Texas 77002

Ladies and Gentlemen:

We hereby consent to the references to DeGolyer and MacNaughton and to the incorporation of the estimates contained in our report entitled “Report as of December 31, 2020 on Reserves and Revenue of Certain Properties with interests attributable to Oasis Petroleum Inc.” (our Report) in the Current Report on Form 8-K of Oasis Petroleum Inc. dated as of February 24, 2021. In addition, we hereby consent to the incorporation by reference of our report of third party dated January 28, 2021, in the “Financial Statements and Exhibits” portion of the Current Report.

Very truly yours,

/s/ DeGolyer and MacNaughton

DeGOLYER and MacNAUGHTON
Texas Registered Engineering Firm F-716