Executive Management


Eric Greager, President and Chief Executive Officer

Mr. Greager joined Bonanza Creek in April of 2018 as President, CEO and member of the Board of Directors. Mr. Greager has 20 years of management experience in the oil and gas industry and previously served as a Vice-President and General Manager at Encana Oil & Gas (USA) Inc. Mr. Greager joined Encana in 2006 and served in various management and executive positions, including leading engineering, geoscience and A&D functions, as well as field operations teams from D&C through production. Most recently, Mr. Greager led Encana’s Western Operating Area, which includes Eagle Ford, San Juan and Wind River assets and served as a member of the boards of directors of Encana Procurement Inc. and Encana Oil & Gas (USA) Inc. In addition, Mr. Greager previously served on the board of directors of Western Energy Alliance, the board of trustees of the Texas Parks and Wildlife Foundation, and the board of managers of Hunter Ridge Energy Services. Mr. Greager received his Master’s Degree in Economics from the University of Oklahoma and his Bachelor’s Degree in Engineering from the Colorado School of Mines.


Brant Demuth, Executive Vice President and Chief Financial Officer

Mr. DeMuth joined Bonanza Creek in November of 2018 as Executive Vice President and Chief Financial Officer. Mr. DeMuth previously served as Vice President of Finance and Treasurer at SRC Energy Inc. from October 2014 until November 2018. Prior to joining SRC Energy, Mr. DeMuth served as Interim Chief Financial Officer of DJ Resources, LLC from August 2013 to September 2014 and as Executive Vice President of Strategy and Corporate Development of Gevo, Inc. from June 2011 to May 2013. Mr. DeMuth currently serves on the University of Northern Colorado’s Monfort College of Business Dean’s Leadership Council. Mr. DeMuth is a Chartered Financial Analyst and received his M.B.A. in Oil and Gas Finance from the University of Denver and his B.S. in Business Administration from Colorado State University.


Cyrus Skip Marter, Senior Vice President, General Counsel and Secretary

Mr. Marter was named Senior Vice President, General Counsel and Secretary in October 2016. During the six months leading up to that time, he assisted Bonanza Creek on a seconded basis while with the Denver law firm of Davis Graham & Stubbs LLP. Mr. Marter previously served as Forest Oil Corporation’s General Counsel for nine years and headed the U.S. legal group at Encana. He began his legal career in 1990 at the Houston law firm of Susman Godfrey LLP and was a partner at the firm from 1996 to 2002. Mr. Marter holds a B.S. in Petroleum Engineering from Texas A&M University and a law degree from the University of Texas Law School.


Dean Tinsley, Senior Vice President, Operations

Mr. Tinsley joined the Company in April 2013 as Production Engineering Manager and was named Vice President – Rocky Mountain Asset Management in May 2015 and Vice President, Operations and Engineering in September 2016. Mr. Tinsley is responsible for all engineering and operations for the Company, including subsurface, drilling, completions, production, infrastructure, and reserves. He has more than 22 years of progressive experience in exploration and production management, operations, and engineering. From 2005 to 2013, Mr. Tinsley held positions as Asset Director for the Piceance Basin and Director of Operations for the Marcellus Region, respectively, with WPX Energy. Prior to this, he held operational, technical, and supervisory roles in three additional basins for Amoco, Barrett Resources, and Williams Production Company. Mr. Tinsley holds a B.S. in Engineering from Colorado School of Mines and an M.B.A. from Colorado State University.


Sandra K. Garbiso, Vice President and Chief Accounting Officer

Ms Garbiso was named the Company’s Vice President and Chief Accounting Officer as well as principal accounting officer in November 2017. Ms. Garbiso is a certified public accountant with over 15 years of accounting and financial management experience. Ms. Garbiso has been with the Company since 2014, during this time she served as the Controller of the Company from June 2016 through November 2017, prior to which she was the Controller at Republic Financial Corporation from January 2013 to January 2014, and was the Financial Reporting Manager at SM Energy Company from December 2007 to December 2012. Ms. Garbiso has an accounting degree from the University of Northern Colorado.