Antonio Calleri has worked in the oil and gas industry for 50 years and holds over 20 patents in engineering and formation evaluation. Antonio has successfully launched and built businesses in over 30 countries. Antonio is currently the Chairman of Geolog, which he grew into the largest independent surface logging company in the world. Previously Antonio held the position of Vice President for Geoservices where he launched and managed services in formation evaluation, drilling (including surface logging, wireline, and hydraulic full-bore DST, well testing, cased/open-hole logging, perforation, PLT, and a PVT laboratory) as well as a number of Early Production Facilities. He has served on the Board of Assomineraria, the Italian Petroleum and Mining Industry Association, and on the Board of SPE Italy.

Antonio holds an Industrial Electronics Engineering degree from the University of Torino, Italy.

Richard Spears has worked in the oil and gas industry for over 40 years and is one of the managing partners of Spears & Associates where he is responsible for leading the firm’s mergers and acquisitions practice. Richard sits on the boards of several privately-owned oilfield service companies as well as serving on the Advisory Board of the Norwegian EV Private Equity firm.

Richard holds an engineering degree from Oklahoma State University and completed graduate work in industrial engineering.

Phil Longorio is a 40+ year veteran of the oil and gas service industry and has held various executive management positions with both major and independent oil service companies. Phil most recently served as CEO and President of Scientific Drilling. Prior to that position, he was the Senior Vice President for TETRA Technologies, Inc. where he was responsible for their Energy Services and Chemicals divisions. Before joining TETRA, Phil served as President and CEO of WellDynamics B.V., a Halliburton and Shell Technology Ventures JV providing intelligent well technology. Previously Phil served as VP of Halliburton for Sperry Drilling. Phil has also served as Non-Executive Chairman and independent director for GeoDynamics, a perforating technology developer, RESMAN, a wireless production monitoring company, and as Non-Executive Chairman and Director for SENSORTRAN, a fiber optics production monitoring company. His career started as a Wireline Logging Engineer for Gearhart Industries. Phil is a United States Air Force veteran.

Dr. Nathan Meehan has worked in the oil and gas industry for 45 years and has held numerous board and senior executive positions in privately owned and publicly listed oilfield service companies, including Vice President of Baker Hughes, President of Gaffney, Cline & Associates and President of CMG Petroleum Consulting. Former President of the Society of Petroleum Engineers and appointed member of the Interstate Oil and Gas Compact Commission by Governors George W. Bush and Rick Perry. He also is a Trustee of the Houston Grand Opera.

Nathan holds a Ph.D. in Petroleum Engineering from Stanford University, an MSc in Petroleum Engineering from the University of Oklahoma, a BSc in Physics from Georgia Institute of Technology and is a member of the National Academy of Engineering.

In May 2023, Nathan is joining the faculty at Texas A&M as a Professor for Petroleum Engineering.

Richard Calleri has worked in the oil and gas industry for 12 years and is currently the CEO of Geolog, a world leader in surface solutions to the oil and gas and geothermal industries. Prior to Geolog, Richard worked for 11 years in Investment Banking in Mergers & Acquisitions, Leveraged Finance and Restructuring, spanning multiple industries including Energy and TMT, holding various positions at global investment banks the last of which being Executive Director at Goldman Sachs, London.

Richard holds an MBA from the University of Chicago Booth School of Management and a BSc (Hons) in Economics from City University, London.

Marcus Oesterberg has worked in the oil and gas industry for 32 years and holds over 16 patents. In 1995 Marcus joined Baker Hughes in Celle, Germany, and relocated to the US in 1997. During his career with Baker Hughes, he worked in various roles in Technical Services, Deepwater Project Management, Repair & Maintenance, Global Marketing, Off- and Onshore Operations, and as the Global Product Management Executive for Directional Drilling. Prior to joining Ignis Energy he was the President of Evolution Engineering, a leading technology provider for downhole MWD tools.

Marcus holds an M.Sc. degree in Mechanical Engineering from the University of Clausthal, Germany.

Franco Caselli is a geoscientist with over 40 years of international experience in the energy sector having previously worked with major and independent oil and gas companies, gaining considerable energy business experience in Southern Europe, Africa, the Middle East, Far East, and South America. Franco has worked across the hydrocarbon, hydrogeology, and renewable sectors as geothermal energy, also managing integrated energy projects with international institutions and governments.

Franco holds an M.Sc. degree in Geology from the University of Florence, Italy.

Sam Abraham has worked in the oil and gas and the geothermal industry for over 30 years, for both operators as well as major oilfield service companies, in South East Asia, New Zealand, East Africa and North America. Sam has managed remote start up projects and worked on regulations for the geothermal drilling industry in Africa, Sam consults for the World Bank as a subject matter expert in geothermal project management and drilling.

Sam holds a M.Sc. degree in Petroleum Technology from Pune University, India and M.S. in Engineering Management from National University, California. Sam is a Ph.D. candidate in Petroleum Engineering from University of Oklahoma.

Cannur Bozkurt has over 12 years of experience in the geothermal industry. She has also worked in the Oil & Gas Industry for 10 years, in both onshore and offshore G & G Departments as an exploration and wellsite geologist and petrophysicist. In 2011, she began her geothermal journey with Transmark Turkey as country manager. In 2017, she joined JESDER, a Geothermal Power Plant Investors of Turkey and was involved in developing geothermal sources. In 2018, she founded Armoni Geothermal Energy Consultancy Services and provided project management services to the geothermal market, including EU project involvements. Additionally, she served as the Manager of TAQA's Geothermal Center of Excellence. Most recently, she was the Managing Director for Enerchange Turkiye.  

Cannur holds a Bachelor of Science in Geology/Hydrogeology Engineering from Hacettepe University and has completed IFP's Geoscience Graduate Diploma Program.

Guy Oliver (Geoscience and Exploration) has worked in the upstream oil and gas industry for 27 years. Guy’s core skills include proven leadership, innovation, a strong technical background with a focus on all aspects of petroleum geology and reservoir geology (fluids and reservoir) and a proven track record of motivating, building and leading multidisciplinary teams focused on regional sub-surface studies. His extensive worldwide experience includes leading and managing exploration through development subsurface projects in NW Europe, North Africa, Middle East Malaysia, Mexico, Brazil, Argentina, Chile and the USA (Alaska & Lower 48).  

Guy holds an M.Sc. in Reservoir Development Geology from Imperial College of Science & technology, London, UK and a Ph.D. in sedimentology and sequence stratigraphy from Plymouth University, UK.