About
Founded by Greg Casillas
Founded in 1986, Casillas Petroleum Corp. (“Casillas”) is a Tulsa-based private and independent oil and gas company owned and managed by Greg Casillas. For the past 37 years Casillas has stayed the course through various cycles of the industry and adapted to the ever-changing canvas. The applied dedication, entrepreneurial, and intellectual knowledge has been the foundation of Casillas to be a successful leader in the oil and gas industry.
Casillas currently operates in excess of 900 wells within 30 counties in Oklahoma and Kansas. Operations have also been conducted in Texas and Louisiana.
Meet the team
Management
Founder and President
Involved in the core management of the company since 1986
Prior to Casillas, Greg received a B.S. in Geology from Oklahoma State University “1983”
Greg serves as an advisor role to Oklahoma State University Geological Department as well as serves on the Board of Governors for the University
Greg Casillas
President
Over 20 years of experience in oil and gas with positions related to M&A, FP&A, and legislative policy
Led financial analysis, reporting and acquisitions with upstream and midstream companies, both public and private of various stages
Experienced leader oil and gas planning and evaluation, with a focus on financial and accounting implications
B.S. in Political Science from the University of Oklahoma and MBA in Finance & Strategy from The Wharton School & Bocconi
John Senger
Chief Financial Officer
13 years of upstream and midstream experience
Extensive E&P and midstream experience across diverse geological provinces, including the Williston Basin, Rockies, Mid-Continent, Ark/La/Tex, West Texas, and Gulf Coast (Texas/Louisiana)
Skilled in petroleum engineering, reservoir/commercial evaluation, asset development, and strategic planning to drive operational efficiency and growth.
B.S. in Petroleum Engineering and M.S. in Finance from the University of Oklahoma
Sean LiSooey
Chief Operations Officer
11 years’ experience in geological sub-surface modeling, inclusive of structural and stratigraphic mapping and depositional modeling
Geo-steered 85+ wells in highly complex structural environment. Total measured depth average greater than 17,500’ per well
Extensive experience in all operational activities from well planning, completion design & day to day producing well operations
B.S. and M.S. in Geology from Oklahoma State University
Clarke Fisher
Senior Geologist
Corporate
Julie Cagle
Controller
Nathan Sterling
Senior DO Analyst
Jon Garrison
Senior Revenue Accountant
Susan Walker
Senior Accountant Kansas
Sara Kelley
Senior Accountant Oklahoma
Patricia Mills
Accounting Associate
36 years
For the past 36 years Casillas Petroleum Corp. has stayed the course through various cycles of the industry and adapted to the ever-changing canvas.
The applied dedication, entrepreneurial, and intellectual knowledge has been the foundation for Casillas to be a successful leader in the oil and gas industry. Although Casillas maintains a lean management structure, it is a highly competitive company and has competed with the much larger mid-cap companies. The success of the Casillas team has resulted in respect and good regard in the industry.
900 wells
Casillas currently operates in excess of 900 wells within 30 counties in Oklahoma and Kansas. Operations have also been conducted in Texas and Louisiana.
1.6 billion barrels
Casillas has drilled and participated in 400+ wells and discovered numerous oil and gas fields within the Mid-Continent region. The total amount of reserves developed through the drill bit has exceeded 1.6 billion barrels of oil equivalent over the last decade. Casillas has pursued both conventional and unconventional reservoirs within our exploration endeavors. The team consistently drives returns by operating efficiently and continues research and development regarding drilling, completion techniques and operations.
$1.0 Billion
Through the various cycles of the industry, Casillas has been opportunistic as an acquirer and seller of assets. With acquisitions in excess of $1.0 Billion. Casillas has acquired assets from both the mid-cap producers as well as major companies. These acquisitions have resulted in significant development of the acquired assets yielding significant distributions to investors.
Midstream
Casillas has not only developed upstream assets but has also ventured into the midstream space. Woody Creek Midstream, a water transportation system that was designed and constructed by Casillas to facilitate the takeaway of produced and treated water of Casillas development in the Scoop Play. This entity was monetized two years after development in excess of a 4X on MOIC.
Strategy
Casillas’ current strategy focuses on acquiring stable, low-risk producing assets, establishing a strong foundation for building a company with world-class resources while delivering significant returns to investors. The company enhances these assets through strategic development and disciplined capital deployment, ensuring that growth is funded within cash flow. By leveraging targeted drilling programs, Casillas maximizes asset potential and drives long-term value creation.