Mr. Sheehan is Chief Financial Officer of Bozeman, MT based Massif Oil & Gas II, LLC.  He previously held the positions of Vice President of Finance at Clearfork Resources where he joined in 2012.  Prior to Clearfork, Mr. Sheehan was the Director of Finance at NFR Energy.  Prior to NFR, Mr. Sheehan was an Investment Banker with Lehman Brothers’ Energy Group in Houston.  Mr.  Sheehan holds an MBA from the University of North Carolina and a BBA in Finance and Accounting from TCU.  Mr. Sheehan is a CFA Charterholder. 

Adam Gollofon P.E.

Chief Operating Officer

Mr. Burdette is Executive Vice President of Subsurface for Bozeman, MT based Massif Oil & Gas II, LLC.  Mr. Burdette has a B.A. from Wittenberg University in Springfield, Ohio and an M.S. in Geology from Wright State University in Dayton, Ohio. Over the last 20+ years, he served in numerous senior technical positions with Amerada Hess, Peoples Energy Production, and Repsol working assets throughout the United States. He last served as the Geoscience Manager for Sabine Oil & Gas. 

Kelly Browning

Office Manager

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EVP Land


Mr. Frizzell is Chief Executive Officer of Bozeman, MT based Massif Oil & Gas II, LLC and brings extensive experience in petroleum engineering and business development to the Massif team. His geographical work experience includes Rockies, Mid-Continent, Ark-La-Tex, South Texas, and offshore GOM.  Prior to founding Massif, he held the positions of Vice President Corporate Engineering and Vice President Northern Region at Sabine Oil & Gas where he joined in 2008.  Prior to Sabine, Mr. Frizzell held various senior technical positions of increasing responsibility with El Paso E&P, Peoples Energy Production, and Amerada Hess.  Mr. Frizzell graduated from Montana Tech with a Bachelor of Science degree in Petroleum Engineering.

what is a massif?

Geologically, a Massif is a section of the earth’s crust demarcated by faults or flexures.  In the movement of the crust, a Massif retains its internal structure while being uplifted as a whole.  A local example of a massif is the Teton range in Wyoming.  Massifs around the world boldly define their landscape.

Ms. Browning is the Office Manager of Bozeman, MT based Massif Oil & Gas II, LLC.  Prior to living in Montana, Kelly previously held the position of Executive Director of Brookdale Absaroka Assisted Living in Cody, WY.   Her business career began in the 1990’s with Marathon Oil Company as Rocky Mountain Region Payroll Coordinator and Finance and Production accounting for Southwest Wyoming field areas.    Her career then followed with business management in the construction industry.   Kelly holds degrees in Business Management and Sociology.    

Our shared vision for creating long-term value and our proven teamwork is the foundation for Massif Oil & Gas.  Much like a Massif in geologic nature, this strong foundation binds us together as we grow.

Mr. Thornquist is the Executive Vice President of Land for Bozeman, MT based Massif Oil & Gas II, LLC.  His vast experience in petroleum land management and commercial real estate are crucial contributions to the Massif team.  Mr. Thornquist began his oil and gas career in 1981 with TXO Production Corporation working the northern Rockies.  In the 7 years prior to joining the Massif team, Mr. Thornquist worked as a landman for both Black Hills Exploration and Resolute Energy Corporation with responsibilities over Western Colorado, NW New Mexico, Northern Montana, and Wyoming.  Mr. Thornquist is a member of the AAPL, NWAPL, and WAPL.

Mr. Gollofon is Chief Operations Officer of Bozeman, MT based Massif Oil & Gas II, LLC. A registered professional engineer, his work experience covers numerous play and field types throughout the Rockies, Mid-Continent, Texas and North African regions. Most recently he managed production and surface operations in the Delaware Basin for Anadarko’s active Wolfcamp development. Prior to that, Mr. Gollofon managed completion and stimulation operations for Anadarko’s Algerian operations including the El-Merk mega-project. Before joining Anadarko, he led exploration and development teams in the northern Rockies for SM Energy. Mr. Gollofon has had extensive experience in designing and operating EOR projects. Mr. Gollofon received a B.S. in Petroleum Engineering with Special Distinction from Montana Tech.

Barrett Frizzell

Chief Executive Officer

Brian Burdette

EVP Subsurface

Scott Sheehan

Chief Financial Officer