GeothermEx Senior Experts and Management
Marcelo has worked in the energy industry with Schlumberger since 1987 as Project Manager and General Manager in Angola, Brazil, Egypt, India, UK, US and Venezuela. He has specialized in improving the operational efficiency of drilling and production systems by integrating multiple services and disciplines at levels, ranging from individual turn-key projects to country-wide operations.
Since becoming GeothermEx company president in 2012, Marcelo has effectively applied this broad experience in technical project execution and management of oil & gas projects to the geothermal market.
As part of the Integrated Project Management group, Marcelo is leading initiatives bringing efficient integrated drilling projects to the geothermal industry as well as integrated exploration and production workflows minimizing risk and maximizes returns to GeothermEx’s clients. In addition, he is actively leveraging relevant technologies developed in Schlumberger’s R&D centers for the benefit of geothermal projects, focusing on drilling efficiency, resource visualization and modeling, improved well targeting, and optimized management of geothermal resources.
Marcelo has a Bachelor’s degree in Electrical Engineering from the Instituto Tecnologico de Aeronautica and a Master’s in Business Administration (MBA) from the Getulio Vargas Foundation, both located in Brazil. For his MBA, Marcelo focused on management of the electricity market. He is fluent in English, Portuguese and Spanish.
Roger is a long-time member of GeothermEx’s staff with expertise applicable to all phases of geothermal exploration, development, management and finance. He has managed and coordinated comprehensive assessments of geothermal resources in dozens of fields, and led several nation-wide assessments of resources in countries such as Nicaragua and India. He has designed and implemented geothermal exploration programs in the U.S. and elsewhere, played key roles in development programs, and performed wellsite geology, technical monitoring of drilling operations, testing and geochemical sampling at more than 30 sites in 14 countries. Roger also specializes in support for project financiers, including the development of financial models, assistance in preparation of loan agreements, design of monitoring programs, and analysis of the economics of existing and proposed geothermal operations.
Roger was awarded a Fulbright Scholarship to study geothermal energy in New Zealand, where he received a MSc degree in Geology from the University of Auckland. He also holds a B.S. degree in Geology from Stanford University. He communicates fluently in Spanish and can read and speak Portuguese.
Mr. Lovekin has worked as a geothermal reservoir engineer since 1985 and joined GeothermEx in 1996. His expertise includes: planning and execution of geothermal well tests; assessment of geothermal reserves and sustainable reservoir capacity; interpretation of well logs, tracer tests, and geochemical trends; design and supervision of well workovers; prevention of scale in geothermal wells and surface facilities; selection of optimal injection strategies for geothermal fields; forecasting reservoir performance and estimating make-up drilling requirements; and budgeting and cost control for drilling and for monitoring reservoir performance. He has been responsible for planning field development and monitoring reservoir performance at numerous geothermal fields in the United States, Indonesia, and Central America.
Before joining GeothermEx, Jim was the Director of Geothermal Resources for CalEnergy Company, Inc., where he managed reservoir engineering, geology, and drilling activities for CalEnergy’s operating geothermal fields: Coso (270 MW), Salton Sea (326 MW), Roosevelt Hot Springs (25 MW), and Desert Peak (9 MW). During this period, he was personally involved in the testing and evaluation of approximately 50 production wells at Coso, where he established a reservoir monitoring program that incorporates flow rate measurements, pressure and temperature surveys, geochemical sampling, and tracer studies. He also coordinated the assessment and development planning for a number of exploratory geothermal projects, including Glass Mountain (Medicine Lake) in northern California, San Jacinto-Tizate in Nicaragua, and the Dieng and Patuha fields in Indonesia.
Jim has a degree in Petroleum Engineering from Stanford University, and is a registered Professional Engineer in Petroleum Engineering in the State of California. He also holds a Bachelor’s degree in Geological Engineering from the University of Nevada, and a Bachelor’s degree in American Studies from Amherst College. Jim is a Board Member of the Geothermal Resources Council. He is fluent in French, can speak and read Spanish, and reads Russian.
In the course of her 30 year career in the geothermal industry, Ann has worked on projects in 26 countries, including more than 50 different geothermal projects that have been developed for power generation (combined capacity nearly 6,700 MW), and an equal number of projects at earlier stages of exploration and development. Her work has focused on providing practical solutions to specific exploration and development issues and determining resource capacity and longevity. Ann also specializes in the evaluation and development of Enhanced Geothermal Systems (EGS), including greenfield projects and the application of EGS techniques to stimulate wells within and around operating geothermal project areas.
Another area of specialization is advising clients about best practices to explore, interrogate, understand and model geothermal resources, and applying her experience to develop effective strategies for mitigating geothermal risks. In this regard, Ann has participated in workshops and presented technical papers at many geothermal conferences, and has suggested technical and policy approaches for managing the unique risks of geothermal power projects for entities such as International Finance Corporation, the US Department of State, and the World Bank.
Ann was awarded a Fulbright Scholarship to study geothermal energy in New Zealand and received an MSc degree in Geology from the University of Auckland in 1984. She received her B.S. degree in Geology from Florida Atlantic University in 1981. Ann is a Board Member for the Geothermal Energy Association, and served on the Science and Technology committee and the International Committee. She speaks French and Spanish.
In the geothermal industry since 1994, Tevfik has been working as engineer and manager for projects in more than 30 different Turkish geothermal fields. After 13 years of implementing geothermal district heating projects across Turkey, he began working on geothermal power projects, first as the Geothermal Reservoir and Planning Manager for Zorlu Energy (focusing on their first expansion at Kızıldere and their new project at Alaşehir), and then becoming the Geothermal Project Manager for Turkish Petroleum International Company (TPIC, the drilling subsidiary of the state oil & gas company TPAO). Through technical and business development activities at TPIC, he had daily contact with nearly all geothermal developers in Turkey, and served as the liaison between the geothermal community and TPIC’s management. Tevfik set up a very successful well testing business for TPIC during this period, and gained important experience in managing operational issues associated with geothermal production, including expertise in mitigating downhole calcium carbonate scaling, a common issue in Turkish geothermal developments.
His significant geothermal experience set the stage for Tevfik’s current position as Geothermal Business Development Manager for GeothermEx and Schlumberger. Although based in Ankara and with a primary focus on Turkish geothermal projects, Tevfik is also responsible for geothermal projects in Europe and Africa, and has participated in projects in Indonesia. Supporting geothermal companies at the stages of exploration, initial drilling, development drilling, and routine project operation, Tevfik’s personal style and geothermal experience combine to make him an effective ally of geothermal developers in Turkey and beyond.
Tevfik received his B.S. in Petroleum Engineering and M.S. in Petroleum and Natural Gas Engineering from the Middle East Technical University, and serves as a part time lecturer in Geothermal Reservoir Engineer in METU’s Petroleum and Natural Gas Engineering Department. He is fluent in Turkish and English.
Minh has worked at GeothermEx as a specialist in numerical simulation since 1991, and now manages the entire reservoir engineering group. His expertise includes analysis of two-phase flow, wellbore simulation, developing numerical simulation software and conducting numerical simulations of geothermal reservoirs. The last is a strong focus of Minh’s work. He has developed original numerical reservoir models of more than 30 geothermal fields worldwide, including several in the United States, Mexico, Central America, Turkey, Kenya, Indonesia, The Philippines and Japan. He has trained reservoir engineers in many of the same countries, focusing on the fundamentals of geothermal numerical simulation, the impact of fluid injection, and special techniques in initial-state modeling, history matching, and future forecasting of well and reservoir behavior. In addition, he has reviewed and critiqued numerical models developed by others on behalf of clients that require an independent second opinion on the viability of a particular simulation.
Prior to joining GeothermEx, Mr. Pham worked for Lockheed Missiles and Space, where he was responsible for modeling heat transfer and conducting fluid dynamics analyses on various components of the heat rejections system to be used in the Space Station, including the heat acquisition sub-system, the heat pipe radiator sub-system and the coolant delivery sub-system. He also worked for the NASA Ames Research Center, where he designed the coating and analyzed heat transfer and fluid dynamics analyses related to the Hard Space Suit AX-5, which will be used in future planetary exploration missions.
Minh has a Master’s degree in Mechanical Engineering from San Jose State University and a Bachelor’s degree in Petroleum Engineering from the University of California, Berkeley. He is fluent in Vietnamese and English.
Minh Pham’s complete CV (PDF)
Stefano is an accomplished drilling engineer who has been active in drilling for geothermal and oil & gas projects continuously since 1991. He is responsible for executing and managing all activities related to geothermal drilling operations on behalf of GeothermEx’s many clients. His expertise includes drilling engineering, well design and drilling programs, drilling rig specifications, well remediation programs, preparation of drilling specifications and bid documents, permitting and coordination with government regulatory agencies, budgeting and cost control for drilling, monitoring and optimizing operational performance and efficiency, supervising drilling operations, field development planning, risk management, well control, and personnel training and development.
In his day-to-day work, Stefano assembles drilling teams, prepares drilling and workover plans, conducts troubleshooting operations, monitors drilling operations remotely and in the field, develops health, safety and environment (HSE) programs for drilling operations, and coordinates the execution of all drilling-related project work. He also manages a number of specific projects that include analyzing and improving proposed drilling programs and advising on procurement issues, particularly for long lead-time items.
Stefano received an MSc degree in Mining and Petroleum Engineering with First Class Honours from the University of Bologna (Italy) in 1990. In addition to his native Italian, he is fluent in English and Spanish.
GeothermEx Senior Advisors
Eduardo has been active in geothermal exploration, drilling, and well testing continuously since 1975, and joined GeothermEx in 1984. He is a renowned expert in geothermal drilling and has worked in at least 40 different countries and a greater number of resources of different types, including dry steam, high- and moderate-enthalpy two-phase fields, and single phase liquid systems. He is a drilling engineer who has designed hundreds of geothermal wells, including pumped and self-flowing full-diameter wells, slim holes and temperature gradient holes for a cumulative total of more than 150,000 m of drilling depth. He has drilled with mud, water, foam and air, and has successfully completed wells to depths exceeding 3,500 m. He has done remedial work, controlled blow-outs, supervised relief well operations, designed and supervised the construction of related civil works (roads, pipelines, drill pads, sumps), and guided many GeothermEx clients through the process of contracting and managing a drilling contractor and procuring drilling equipment and services.
In addition to this long geothermal drilling experience, Eduardo has taught many courses on drilling and well testing for clients all around the world. He also has expertise in regulatory issues related to drilling, and has participated in devising appropriate regulations to govern geothermal drilling and development in several countries.
Eduardo has a Master’s degree in Petroleum Engineering from Stanford University and a Bachelor’s degree in Civil Engineering from the University of Costa Rica. He is fluent in Spanish and English, and speaks and reads French and Italian.
Chris has been with GeothermEx since 1974 and is an expert in geochemistry, geology and conceptual hydrogeologic modeling of geothermal resources, in which he interprets and integrates geological, geochemical, drilling and well testing data. He has worked on geothermal geochemistry in nearly every country in the world that has active geothermal resources, undertaking such tasks as design of sampling and analysis programs, field measurements and sampling, design of field laboratories, training field and lab personnel, monitoring results for quality control, and interpreting results. His results are used to help specify the operating set-points for geothermal power plants in a way that optimizes resource use while minimizing issues associated with non-condensable gases, corrosion and scaling (calcium carbonate on the production side, and silica on the injection side). Chris also has experience in designing geochemical software and geothermal databases (which he has developed for several major geothermal regions, including the western United States, Mexico and Central America, Chile, and several other regions. He has also taught numerous geochemistry courses at industry conference short courses and for individual clients needing to train a group of people in geothermal geochemistry.
Chris has a Ph.D. in Geology from Harvard University and a Bachelor’s degree in chemistry from the University of California, Berkeley. He is fluent in Spanish and English.
Jim McNitt has been a leader in geothermal exploration and development since 1959, when he completed his PhD and became the first geothermal specialist for the California Division of Mines and Geology. In this position, he developed the first comprehensive geologic map of The Geysers geothermal field, initiated state-funded exploration in the Imperial Valley, and provided technical input to the development of the first geothermal regulations in the United States. He left California for a geothermal position at the United Nations, where he was responsible for reconnaissance and detailed exploration activities in El Salvador, Honduras, the Hashemite Kingdom of Jordan, Ethiopia, Kenya, Madagascar and India. His work led to the discovery of the several fields, notably including Kenya’s Olkaria field, where he sited and drilled the first productive well in the field. Olkaria currently has more than 100 wells and produces nearly 500 MW of geothermal power, ranking among the world’s most prolific geothermal fields.
Jim left the UN to join GeothermEx in 1980 as the Vice President for Exploration. In this position, he managed exploration programs, supervised drilling operations and geologic data collection, synthesized and integrated data to develop conceptual hydrogeological models, and selected well sites and drilling targets in at least 50 different geothermal reservoirs. He has a remarkable track record of successfully siting discovery and step-out wells in numerous geothermal fields. Since his retirement in 1997, Jim continues to work on projects of interest, including many at the early exploration phase.
Jim has a Ph.D. in Geology from the University of California, Berkeley, a Master’s degree in Geology from the University of Illinois, and a Bachelor’s degree in Geology from Notre Dame University.
Jim McNitt’s complete CV (PDF)
More GeothermEx Experts
Logan’s expertise includes geochemical field methods and evaluation techniques, structural and stratigraphic geology and field geologic methods, mineralogy, well drilling, well logging, well testing, conceptual/ hydrogeologic modeling, and field program and project management and budgeting. He works with fluids sampling at springs and wells, fluid and gas chemical data interpretation, computer database management and graphical displays of geochemical and geologic data, isotope chemistry, field analysis equipment design and fabrication, geologic and geochemical resource model creation and depiction, and resource drilling and development planning. He has extensive geothermal experience in the United States, Turkey and Indonesia, among other countries.
Prior to joining GeothermEx, Logan served as a wellsite geologist and well logging geologist for two leading mud logging companies, working on rigs drilling geothermal and oil & gas wells. Logan holds a Master’s degree in Geochemistry from the Colorado School of Mines and a Bachelor's degree in Environmental Science (geology specialization and chemistry minor) from Drexel University in Pennsylvania. Mr. Hackett is a certified Professional Geologist in the state of Wyoming. He speaks and reads Spanish and French.
William has experience in various aspects of geothermal drilling, including well design (casing, cementing, directional planning, drilling fluids – including aerated drilling, well control, etc.), preparation of drilling programs and AFEs, wellsite safety, well testing and daily field operations. He has extensive knowledge of all phases of geothermal exploration drilling, including slim-well and temperature-gradient well designs in addition to large-diameter production wells. He has managed or assisted with drilling and well testing operations in several countries, including Indonesia, Argentina, Portugal (Azores), Turkey and the US, often serving as the liaison between drilling operations on-site and company management in the home office, ensuring that the drilling program is carried out as planned and within budget, or appropriately modified based on actual drilling conditions.
Initially trained as a geologist, William’s expertise also includes geothermal resource exploration and evaluation, analysis of subsurface geology, well target selection, coordination and execution of geothermal well site geology and logging, coordination of well testing, tectonic geomorphology, fault characterization, watershed hydrology and mountain-block recharge, and the coordination and interpretation of electromagnetic surveys. Following the completion of his MS degree, William worked extensively in the geothermal fields of the Imperial Valley, in southern California.
William has a BS in Geological Sciences from San Diego State University and an MS in Earth Sciences from CICESE (Centro de Investigación Científica y de Educación Superior de Ensenada) in Mexico. He also has extensive drilling training, including internal guidance under Eduardo Granados and Stefano Scagliarini, and several courses, namely: Operational Drilling Technology and Advanced Well Control at the Murchison Drilling School (2012), IADC Well Control Accreditation Program (Certificate Number: A402651) at the Murchison Drilling School (2012), IWCF Drilling Well Control Program Surface BOP Stack Level 4 (April 2015 – Certificate Number: DL4S00044870-01-EKY7), Stuck Pipe Prevention Course, and a Drilling Course at the University of Texas Petroleum Extension Service (PETEX). William is an active member of the Geothermal Resource Council and is fluent in English and Spanish.
Rob has been working continuously in geothermal projects since 2007, one year before he joined GeothermEx. His main focus is on the design and execution of well tests, and analysis of well test data. Rob has designed and conducted production tests, injection tests, multi-well interference tests and tracer tests and has evaluated data from all of them. Recent examples include isochronal testing of single-phase steam wells at The Geysers and interference testing of a group of single-phase liquid wells at a project in Nevada. Rob has also developed hydraulic stimulation programs for low-permeability geothermal wells, in support of two Enhanced Geothermal Systems (EGS) projects in Nevada.
In addition to his well testing expertise, Rob is highly skilled in numerical reservoir simulation, and has recently developed numerical reservoir models of three producing fields in Mexico and several in the United States. He has worked closely with the developers of geothermal reservoir simulation software to improve performance and expand capabilities. He performs economic and risk analyses of geothermal projects to help GeothermEx’s clients make informed informed investment decisions. He has worked in the high Andes of Chile, and has resource evaluations, reserve estimations and resource due-diligence on four fields in East Africa: Longonot and Suswa (Kenya), and Corbetti and Aluto-Lagano (Ethiopia).
Rob has an Engineer’s degree in Energy Resources Engineering and a Master’s degree in Petroleum Engineering, both from Stanford University in California.
Since joining GeothermEx in 2011, Raysa has worked on numerous projects in the western United States, Central America, South America, the Philippines and Indonesia, adapting her hydrogeology skills to the geothermal environment. Her work at GeothermEx has focused on finding geothermal “signatures” in water well databases (for reconnaissance exploration projects in California, Idaho and Washington), spatial analysis of geothermal data using 3D modeling techniques (for nearly every project GeothermEx undertakes) and integrating traditional geothermal analyses with modern analysis and visualization techniques. Raysa is remarkably proficient and accurate in finding, preparing, organizing and analyzing geospatial data, and utilizes several useful data formats, depending on the client’s need and the type and quantity of data. Using Schlumberger’s PETREL* E&P platform, she routinely prepares 3-D models that highlight geologic, geochemical, geophysical, temperature and permeability data. The results are often used to identify well sites and drilling targets. She also has experience in well testing, instrumentation and downhole measurements in geothermal wells, and has participated in several major geothermal market studies, including situational analyses (legal, regulatory, financial), surveys of existing geothermal projects, field-by-field breakdowns of status and activities, and geothermal growth forecasts.
Prior to her tenure at GeothermEx, Raysa worked with Schlumberger Water Services, working on organizing and analyzing large sets of hydrologic data, GIS mapping, well testing and monitoring, water well instrumentation, field data collection, and groundwater modeling. Raysa has an MSc in Hydrogeology from the University of Nevada (Reno), and a BS in Environmental Science from the Universidad de Puerto Rico, Río Piedras. She is fluent in English and Spanish.
Employed by GeothermEx since 2007, Amber has a highly useful skillset. She has significant experience in the collection, research, interpretation and integration of geoscientific data from geothermal fields. She is adept at preparing GIS databases, analyzing geospatial data and cartographic design (including detailed geologic maps, cross sections, and stratigraphic sections). She has significant experience with PETREL* E&P, Schlumberger’s 3-D analysis and visualization platform. Amber has worked as a wellsite geologist on numerous projects, and this has enabled her to gain significant experience in well logging, well testing, instrumentation and downhole measurements in geothermal wells. In two Enhanced Geothermal Systems projects, Amber participated in the collection, management and analysis of data from hydraulic and chemical stimulations of low-permeability geothermal wells.
In addition, Amber is extensively trained in operational health and safety, including standard safety procedures for clean-ups or emergency response operations involving hazardous materials. She helps the GeothermEx team to prepare HSE plans for field projects, and has managed all internal HSE activities for GeothermEx since 2012.
Amber has a BS in Geology (with distinction) from Sonoma State University in California, received a GIS Certificate in Environmental Analysis from the College of Extended Learning at San Francisco State University in 2013, and is a Registered Geologist-In-Training in the State of California (Certificate Number 317).
Michelle has been involved with geothermal power generation since 1995 and joined GeothermEx as Reservoir Engineer in 2014. Her areas of expertise include analysis of geothermal well tests, numerical reservoir simulation, thermodynamics, fluid mechanics, multi-phase flow in porous media, geothermal resource assessment, monitoring and evaluation of drilling and resource development.
Michelle has a Master’s degree in Petroleum Engineering from Stanford University, and a Bachelor’s degree in Chemical Engineering from the University of The Philippines.
Tito is a Senior Geologist with GeothermEx, Inc., and SIS Data Services Technical Team Lead with Schlumberger’s Software Integrated Solutions – California Basin, USA. Tito’s areas of expertise include geothermal resource exploration and evaluation, analysis of subsurface geology, and borehole image log interpretation (comprising fracture and fault characterization, sedimentary feature identification and textural analysis, sedimentology and sequence stratigraphy interpretations, completion optimization, multi-scale structural interpretation, porosity analysis in carbonate reservoirs, unconventional reservoir characterization, and comprehensive analysis with other subsurface data). Tito is also actively involved in sales, marketing, job planning, monitoring, quality control, and advising on many aspects of Schlumberger’s geology logging tools.
Tito earned Bachelor of Engineering, with cum laude predicate, from Gadjah Mada University in Indonesia in 2006. He has been an active member of the Young Professional Coordinating Committee of the SPE International. He is fluent in English, Bahasa Indonesia, Javanese and Malay.
Erika’s experience has been working primarily in petrophysics since 2001, leading many integrated geo-technical interpretation projects and teams. Now with GeothermEx, Erika is supporting technical due diligence projects including a focus on low-temperature systems that often rely on data from petroleum exploration. She has worked with most types of sensor data; providing an understanding of the application, quality control, and limitations for correct use. Senor data includes; wireline, cased-hole, and LWD including but not limited to; acoustic, formation micro resistivity images, magnetic resonance, elemental capture spectroscopy, formation testing, core analysis, production logging, well integrity, nuclear and resistivity. Her work has included integrated petrophysical model creation with data normalization in petroleum brown fields with decades of historic data. Erika has also worked with neural network enhanced data expansion where limited modern data is expanded to enhance older broad but limited datasets. Specific areas of advanced petrophysical projects include; wellbore geomechanics, sanding prediction, sonic derived wellbore fracture detection, resistivity image structure, fracture and thin bed analysis. Erika has also supported job planning and data interpretation of fiber optic distributed temperature surveys (DTS).
Erika has a Master’s degree in Hydrology and Bachelor’s degree in Geology from New Mexico Institute of Mining and Technology.