Extraction Oil & Gas Inc. on March 5 said the head of the Denver-Julesburg (D-J) Basin-focused E&P had left the company.

Mark Erickson, who has served as chairman and CEO of Extraction since founding the Denver-based company in 2012, has stepped down, effective March 4. Erickson has been on a medical leave of absence since April 2019, according to a company filing with the U.S. Securities and Exchange Commission.

As a result, Matt Owens has been appointed as CEO, a position that he had held in an interim capacity since Erickson’s leave of absence a year ago.

Owens has been with Extraction since its formation and previously was with PDC Energy and Gasco Energy. In addition to his appointment, he will also retain his current roles as president and member of the board.

Additionally, Extraction named Thomas B. Tyree Jr. as executive chairman.

Tyree serves as a non-executive chairman of the board of Northwoods Energy LLC, a private oil and gas company with assets in Wyoming’s Powder River Basin that he founded. He also serves as a director on the Antero Resource Corp.’s board.

The changes in leadership roles are effective March 4, according to a company news release.

Extraction operates in the Wattenberg Field of the D-J Basin where it plans to remain focused on generated free cash flow with a 2020 capex  of between $485 million and $555 million.