IRT Associates


Prior to their association with IRT, all of our Senior Associates gained extensive experience with operating companies and/or other major international consulting companies. Years of experience, as stated herein, equates to years of industry or related experience since graduation and includes post-graduate studies. Detailed resumes of all our personnel including several consulting associates not included here are available upon request.



Dr. John F. Arestad (Senior Consultant - Geophysics / Geology) has over 40 years' experience in the energy and minerals industries, possessing a strong background in overall exploration, development and reservoir characterization strategies with an emphasis on geophysics and geology. He has expertise with many geophysical methods and is solidly familiar with several others as applicable to South America, Mexico, Yemen, Kuwait, Denmark, Australia, Rocky Mountains, Gulf Coast, Gulf of Mexico and California; as well as shallow seismic reflection and environmental/land use projects in Nebraska, Alabama, California and Oklahoma. Dr. Arestad has managed seismic reflection projects including survey design, implementation, data processing quality control and interpretation. He uses personal computers and UNIX workstations extensively for database management, economic evaluations, geological and geophysical data interpretations/analyses utilizing Landmark, ProMax, GeoGraphix, IHS Kingdom, Petra, Hampson-Russell and other software.


Mr. Chad Baillie (Senior Consultant - Reservoir Geophysicist) has 11 years of professional experience working on reservoir characterization and interpretation projects using an interdisciplinary approach, collaborating alongside with geologists, engineers, and geophysicists to solve challenging reservoir problems. Specialize in multivariate statistics by integrating 3D seismic attributes, rock mechanics, microseismic, engineering and geologic data to optimize completion and well performance. Most of my experience has been focused in unconventional and conventional reservoirs and the development of existing fields.


Mr. Leszek Bednarski (Senior Consultant - Geologist / Petrophysicist) has over 10 years of experience in the oil and gas industry as an exploration geologist and petrophysicist in both conventional and unconventional reservoirs. Specializing in well log interpretation and analysis as well as in the integration of petrophysical and seismic attributes through rock physics analysis. Combining broad geological and petrophysical knowledge together with field experience in well drilling to generate a better understanding of the reservoir characteristics.


Dr. Deryck J Bond has 35 years’ experience in the oil and gas industry. After a period in research, he has worked in petroleum and reservoir engineering positions, mainly with operating companies. He has expertise in reservoir simulation, reservoir characterization and petroleum economics and has acted as an advisor to senior management. Additionally, he has taught reservoir management courses. He has worked in Europe the Middle East and Africa and is currently based in Kuwait.


Ms. Lisë Brinton  (Senior Associate Consultant - Geoscience) has over 28 years experience in sedimentology, petrography, and strgraphy applied to petroleum exploration, field development, and reservoir characterization. She is recognized for her experience in core description and thin section petrography in carbonate, mixed carbonate-clastic, and clastic depositional systems and has worldwide experience in interpreting core and petrographic information for integration and application to complex, multidisciplinary, exploration and reservoir studies. Ms Brinton has extensive project experience in the application of sequence stratigraphic concepts, depositional systems and diagenesis modeling, recognition and evaluation of complex geologic relationships, and controls on petroleum reservoir occurrence and distribution. Her professional experience includes projects in the United States, Tunisia, Algeria, Morocco, Bulgaria, Italy, Abu Dhabi, Kuwait, and Colombia.


Mr. James Colliton  (Senior Associate Consultant - Petrophysics) has 42 years of petrophysics and geology experience evaluating diverse reservoirs for exploration, appraisal, and development projects. He has an extensive skill set in formation evaluation, integrating open-hole wireline logs with core analysis and production performance. Jim has demonstrated success in the development of petrophysical models for reservoir characterization and asset evaluations; reservoir quality assessments for deep-water exploration; exploration petrophysics for “Missed Pay”; testifying as an Expert Witness; log quality control; core program selection and core analysis; and provided support for unconventional shale, tight sands, and EOR projects. In addition, Jim has mentored, led, and collaborated with many individuals and teams within the oil and gas industry.


Mr. Terry B. Eschner (Senior Associate Consultant - Geoscience) Mr. Eschner is a geologist with over 24 years of experience in exploration and production, prospect generation and evaluation, structural analysis, sequence stratigraphy, core studies, sedimentology, seismic interpretation, reservoir characterization and reservoir management. He has a strong background in the thrust belts of Colombia, Bolivia, Argentina, Wyoming and Montana. He has exploration and production experience in Algeria, Kuwait, Mexico, Colombia, Venezuela, Bolivia, Argentina, Guyana, and many basins in the U.S.A. including those in the Mid-Continent, California and Alaska. He is highly skilled in prospect generation and evaluation, identifying deeper-pool, step-out and behind-pipe opportunities, regional and field-scale structural analysis, siliciclastic core description and the integration of geological, geophysical, petrophysical and engineering data. He has strong expertise in working with deposits from various depositional environments, particularly eolian, fluvial, deltaic and shallow marine. He has used the Statistical Curvature Analysis Technique to evaluate dipmeters from hundreds of wells.


Ms. Laura Foulk (Senior Associate Consultant - Geoscience) has over 30 years experience in the oil and gas industry. For the past 25 years she has specialized in the interpretation of wellbore images. Having interpreted images from a variety of tectonic and depositional settings worldwide, she focuses on extracting the structural and stratigraphic information obtained through image interpretation and integrating those data with petrophysical, geologic and geophysical data. She routinely uses image data to correlate core to logs, and perform geologic and petrophysical interpretations. In addition to her interpretation work, she teaches domestic and international courses on structural and stratigraphic interpretation of wellbore images. She has worked on reservoir characterization projects worldwide, including recent projects with the tight gas sandstone of the Rocky Mountains, fractured shales of the Devonian and Ordovician, Permian Basin carbonates, Deep Water Gulf of Mexico turbidites, carbonate and clastic systems in Kuwait, Columbian fluvio-deltaics, Hungarian Miocene clastics with volcanic tuffs, and mixed tectonic systems of California.


Mr. Brian Glater (Senior Associate Consultant - Petoleum Engineer) specializes in production and reservoir engineering, with experience in software integration, data analysis, project management, and personnel management in remote locations with diverse, multi-disciplinary teams. A technical leader; adding value through increased production and reduced costs in various disciplines.


Mr. George Grinestaff (Senior Associate Consultant - Engineering) is a reservoir engineer with expertise in reservoir modeling and simulation. He has also worked on drilling rigs, operated wells, surface facilities and the design, planning, and execution of horizontal wells. He has a unique gift to understand reservoir mechanisms, wells, and coupled facilities, which accurately predict performance of oil and gas plays.


Mr. David Hoffman has over 45 years of professional experience as a petroleum geologist. His career includes extensive domestic and international experience with major integrated companies (Amoco, Arco), mid-size companies (Maxus Energy, Occidental), independents (Roy M. Huffington), and NOCs (Saudi Aramco, Qatar Petroleum). Dave has exploration and development experience with both clastic and carbonate reservoirs in the USA, Venezuela, Bolivia, Ecuador, Colombia, Argentina, Saudi Arabia, Bahrain, Oman, Qatar, the UAE, and Indonesia. His technical specializations include advanced 3D geocellular modeling, petrophysics, numerical simulation for IOR/EOR projects, geotechnical data management, exploration new ventures, field studies, and reserves evaluations. Dave earned his BSc in Geology at California State University Sonoma, and his MSc in Geology at San Diego State University, and has been a member of the AAPG since 1972 (CPG# 2972).


Dr. Darrell Kramer (Senior Associate Consultant - Geophysics) is an innovative, problem solving geoscientist skilled in multiple disciplines of geology, geophysics and petrophysics. He has over 30 years of experience in the geoscience field, both within the mining and oil and gas industries. Dr. Kramer has worked and managed cross-functional teams in the areas of exploration and development. He is familiar with clastic and carbonate environments in both conventional as wells as resource plays. His background includes positions in research, teaching and mentoring, and has worked both domestically and internationally.


Mr. Bruce Laughlin has 35 years. of reservoir and production related experience, 15 years as a team leader and project manager, within mature oil and gas field development, reservoir management, and production operations, located in Alaska, North Kuwait, South Texas, Gulf of Mexico, California and Colorado. This experience includes lead reservoir engineering expertise in field development studies and reserve analysis. Bruce is an expert witness recognized by the State of Alaska for EOR and gas monetization.

Additionally, Bruce brings capability in change-management initiatives crystallizing new methods for rig workover management and field development. He has demonstrated supervisory and leadership skills, with the ability to train/mentor a wide experience level and discipline range of individuals. Bruce has managed cross-functional teams, meeting time critical deadlines while enforcing quality and safety standards. With his management skills, he can manage the entire project scope, from conception to implementation through completion. His focus and expertise is based on Safety, People, Near Term Cashflow and Resource Pull through.


Mr. David List (Senior Associate Consultant - Geology) is a petroleum geologist/geophysicist with over 30 years of technical and project management experience working in interdisciplinary teams. Generated and evaluated stratigraphic prospects and developed fields in the Rocky Mountains (Williston, Powder River, Paradox, Red Desert, Big Horn and Green River basins). Experience in Argentina, Columbia, Venezuela, Mexico, Algeria, China, and Kuwait. Adept at interpreting and integrating geologic, geophysical, petrophysical, and engineering data into consistent geologic models for development and exploratory purposes. Skilled in the use of workstations for databasing, seismic modeling, velocity modeling, seismic interpretation, log correlation, stratigraphic and structural analysis, and mapping. Strong background in developing and implementing innovative and efficient workflows for streamlining reservoir characterization and exploration projects. Experience with fractured and conventional reservoirs, clastic and carbonate depositional environments in a variety of structural settings.


Ms. Rachael Mays (Senior Associate Consultant / Petrophysics) has over 28 years of valuable petrophysical experience which was acquired worldwide in a variety of working environments. She has also worked as a senior consulting petrophysicist working a wide variety of both domestic and international projects for large national oil companies to small domestic operators. In addition, she is highly proficient at performing single well or full field reservoir studies integrating log analysis, core description, reservoir fluid properties, well test analysis, completion history, and production data. Ms. Mays has been fully responsible for the design and implementation of innovative log and coring programs, meeting all objectives while minimizing cost and risk.


Dr. Katie-Joe McDonough (Senior Associate Consultant / Geology) is a geological/geophysical consultant specializing in sequence stratigraphic and seismic interpretation applied to exploration and production. Dr. McDonough pursues thorough integration of multiple data types (outcrop, core, well log and seismic) to arrive at rigorous and consistent stratigraphic/sedimentological interpretations. She has explored in siliciclastics and carbonates in shallow to deep marine settings of various basins of North and South America, offshore West Africa, the North Sea, Indonesia and East Africa, and has conducted in-house sequence stratigraphy short courses for the industry. She has over 19 years of experience in the petroleum industry including staff, consulting and mentoring positions with Exxon USA, Mobil, Elf Acquitaine, EcoPetrol, Cimarex Energy, MedcoEnergi Jakarta, Noble Energy, Anschutz Exploration, Enerplus and ION Geophysical. She is an active member of AAPG (2001 Annual Conference Organizing Committee), DGS, RMAG, SEPM-RMS, SEG, WTGS. She received her BS and degree in Geology (Geophysics Option) from the University of Texas at Austin, and her MS and Ph.D. in Geological Engineering from the Colorado School of Mines (dissertation : Stratigraphic architecture of the Vercors carbonate ramp: Linked clinoform geometries and facies differentiation ...) She has also served as adjunct faculty teaching stratigraphy at Colorado School of Mines.


Mr. Ron Mossbarger (Senior Associate Consultant - Engineering) has over 35 years of experience in the areas of reservoir and pipeline simulation, including long stints with Chevron, Scientific Software . Intercomp and Halliburton. He has extensive experience with Nexus, VIP and Eclipse and has worked with many clients worldwide, with emphasis in the Middle East, North Sea, offshore Africa and the Gulf of Mexico. In addition to traditional reservoir simulation, Mr. Mossbarger has been involved in a large number of Integrated Asset Management projects coupling reservoir and surface facility modeling for full-field predictive modeling.


Mr. Chet Paris (Senior Associate Consultant - Geology) is a petroleum geologist who has spent over 30 years discovering and maturing oil and gas fields with both major and independent petroleum companies in the Rockies, Alaska, Gulf of Mexico, and the North Sea. He uses a "Big Picture" approach and his breadth of experience and networking to integrate geology, geophysics, and engineering into profitable oil and gas opportunities.


Dr. Eric S. Pasternack (Senior Associate Consultant - Petrophysics) has over 37 years of experience in petrophysics, well log interpretation of open and cased-hole wireline log data, and integrated reservoir studies. Dr. Pasternack is recognized for his Russian log expertise and training in the interpretation of Russian logs. He has also provided support for unconventional plays and CO2 EOR programs.


Jerry Schwinkendorf (Associate Consultant - Geology) specializes in full 2D and 3D seismic data processing as well as sub-surface imaging of land and marine projects.


Julie Shemeta (Senior Associate Consultant - Geophysicist) has over 25 years of industry experience including oil and gas, mining and geothermal. Her expertise includes microseismic and earthquake acquisition, processing, interpretation, and data integration across multiple industries. She has worked on tight gas and unconventional oil projects in North and South America, Australia, and Europe and applied surface, borehole, and fiber optic data acquisition methods. Her knowledge includes planning, data processing QC, and interpreting data in microseismic mapping of hydraulic fractures. She was selected to be a member of the National Research Council study on Induced Seismicity published in 2013, and since then, has been actively involved as a consultant to regulators and oil and gas operators on induced seismicity issues. She is an expert user of the Transform software platform, and was involved in the application's development. As an expert witness, she has testified on a variety of subjects, including cases related to hydraulic fracturing "frac hits", solution mining cavern failure, and land conflicts. Julie was a member of Society of Exploration Geophysicists (SEG) The Leading Edge Editorial Board from 2014-2017, serving as Chairman in 2017. Julie is also volunteers with the Denver Geophysical Society.s 3D Seismic Symposium committee since 2005 and served as the meeting co-chairman from 2008-2011. She was awarded with a SEG Special Commendation Award in 2017.


Ms. Susan Starr (Senior Associate Consultant - Engineering) is a reservoir and production engineer with over 35 years in the industry. She is a principal partner and owner of an oil and gas consultancy specializing in asset evaluation, reserves progression, front end project appraisal, and organizational design. Her experience in engineering, management and executive leadership in major integrated oil and gas companies includes BP, TNK-BP, and Conoco. Extensive US and international experience in Russia and the FSU, North Sea, Canada, Alaska, and the Gulf of Mexico Shelf.


Mr. David Szabo (Senior Associate Consultant - Engineering) is a principal partner and owner of an oil and gas management consultancy specializing in asset evaluation, reserves progression, front end project appraisal, and organizational design. Mr. Szabo has over 36 years. experience in engineering, management and executive leadership in major integrated oil and gas companies including BP, TNK-BP, and Marathon, as well as extensive US and international experience in Russia and the FSU, West Africa Angola offshore, Middle East Kuwait, North Sea, Canada, Alaska, and the Gulf of Mexico Shelf and Deepwater.


Mr. Kevin Turco (Senior Associate Consultant - Geoscience) has over 33 years petroleum industry experience with an ongoing emphasis on integrated reservoir studies. He has been a proven and insightful contributor in all geologic aspects of reservoir studies including mapping, geocellular modeling, volumetric and reserve studies, depletion planning, well planning and operations, field surveillance, risk analysis, and core studies. His experience and training is with two international operators and positions include geologist, petrophysicist, geocellular modeler, operations, and various leadership positions. He has considerable experience in both clastic and carbonate reservoirs in the Shelf and Deepwater Gulf of Mexico, Permian Basin (TX-NM), East Texas, Gulf Coast, Gulf of Suez (Egypt), Llanos Basin in Colombia, Alaska North Slope, Canadian Tar Sands, and the West Siberian Basin.


Ms. Welker-Haddock (Senior Associate Consultant - Geoscience) is a proven oil finder in multiple US and international arenas, including 7 years of expatriate experience. Experienced in all phases of exploration, appraisal and field development including 3-D geo-cellular modeling. She has broad technical knowledge and workstation skills, project management experience, strong presenter to management, partners and host governments.


Mr. Craig Williams (Senior Associate Consultant - Reservoir Engineering) is an engineer with over 40 years’ experience in designing and conducting reservoir studies. Recently, Craig was team leader for Occidental’s Advanced Reservoir Management Group (ARM), responsible for reservoir design of CO2-EOR projects in the Permian, including source field exploitation, and sequestration with CO2-EOR. Prior to Occidental, Craig was a consulting reservoir engineer, with international experience including both National and Commercial Companies. Engineering specialties included dual porosity (naturally fractured) simulation, and compositional simulation. He has also designed multi-field projects where best surface facility design was the objective. Major project experience includes Europe (UK, Germany, Romania), Africa (Algeria, Egypt, Gabon, South Africa), Kuwait, Mexico, Colombia, and Australia, and in the USA (Alaska, California, New Mexico, Wyoming, Texas, Colorado).


Mr. Donald J. Yezerski (Senior Associate Consultant)