Our Team

About our experts

TerraEx Group is a team of associated Geoscience experts, all renown in their respective fields and with extensive experience in training, consulting, field projects and software modeling. Experts create onsite and online modules, coach and support clients in their workflows and consult on projects.    

Team of Experts

Catalina Luneburg, PhD


Structural Analysis and Modeling, validation of petroleum systems worldwide applying section balancing, 2D/3D restorations, HC reserve estimates, 3D framework models and fracture analysis. 

Catalina Luneburg's Bio
Catalina Luneburg is the owner and director of TerraEx Group LLC and responsible for developing and promoting the new services model as well as daily operations.
She is a recognized Structural Geology expert in the validation of a variety of basins and petroleum systems worldwide, focusing on geologic interpretation and validation, Structural Geology modeling, cross section balancing and 2D/3D time-step restorations as well as HC reserve estimates, 3D framework building and fracture prediction analyses.
Previously, Luneburg was a Product Manager and Senior Scientist at Landmark/Halliburton developing geomodelling workflows and managing/designing software applications such as LithoTect and DecisionSpace. She has also held positions with GeoLogic Systems and Midland Valley, and spent many years in academic teaching and research.
Luneburg holds a doctorate in Natural Sciences from the Swiss Federal Institute of Technology in Zurich, Switzerland, and a master’s degree (Diploma) in Geology/Paleontology from the Ludwig-Maximilian University in Munich, Germany.  
She has published extensively in her field including several books, and has authored a number of patents. She is fluent in English, German, and Spanish, and proficient in French and Italian.

Jim Granath, PhD

Associated Expert

Structural analysis, cross section construction and balancing, seismic interpretation; tectonics and regional geological synthesis in compressional and extensional settings; petroleum play analysis  

Jim Granath's Bio
Jim Granath is a consulting structural geologist based in the Denver, Colorado, area.  He holds his PhD from Monash University in Australia, and a BS and MS from of University of Illinois at Champaign-Urbana.  He specializes in structural analysis at all scales, hard and soft rock: traditional techniques as well as modern cross section construction/restoration, seismic interpretation; tectonics, and regional geological synthesis.   Current research interests include intraplate block faulted terrains, both extensional and compressional, regional tectonics of Africa, and the Kurdistan thrust belt.    He had 18 years of industry experience in a major in research, exploration and new ventures roles.  He opened his consulting practice in 1999, focusing it on structural geology and tectonics as applied to exploration problems. He is on the Graduate Faculty of the University of Alabama, Tuscaloosa.  Over the years he has worked on projects in some 40 countries, and is the author of numerous research papers and co-edited several multi-author compendia.

Bob Ratliff, PhD

Associated Expert

Structural analysis and Structural restorations of numerous tectonic settings and HC systems worldwide, original developer of LithoTect software and renown instructor

Bob Ratliff's Bio
Bob received his PhD in structural geology from the University of Colorado in 1992 and has BS and MS degrees in geology from Wayne State University. He was one of the first employees of Geo-Logic Systems Inc., in charge of worldwide consulting projects and GeoSec implementation. From 1992-1998 he was Assistant Director of the CogniSeis Development Boulder Center where his responsibilities included the technical content and marketing of the GeoSec, GeoSec3D, and GeoStrat computer programs. Bob rejoined GLS in 1998 as Director of Product Development, overseeing initiation and development of the widely-used LithoTect structural analysis software. In 2009 he continued in that role as a Product Manager for Landmark Software and Services (Halliburton), retiring in 2014 to pursue independent consulting and research. Dr. Ratliff has lectured worldwide, at various universities and throughout the petroleum industry, on the geometry, kinematics, and interpretation of rock deformation, and has been an instructor for the AAPG Workstation Interpretation of Structural Styles course as well as the Nautilus Seismic Interpretation Field Seminar.

Mark Rowan, PhD

Associated Expert

Salt Tectonics, i.e. styles/kinematics of salt, salt-sediment interaction, architecture/evolution of passive margins, applications to petroleum exploration.

Mark Rowan's Bio
Mark received a B.S. in biology from the California Institute of Technology in 1976, an M.S. in geology from the University of California, Berkeley, in 1982, and a Ph.D. in structural geology from the University of Colorado at Boulder in 1991. He worked for Sohio Petroleum Co. (1982 to 1985), Geo-Logic Systems (1985-1989), and Alastair Beach Associates in Glasgow, Scotland (1989-1992). He then returned to the University of Colorado as a Research Assistant Professor before founding his own company in 1998, where he consults and teaches for the petroleum industry worldwide and conducts research sponsored by industry.
Although Mark’s background includes many types of tectonic environments, his primary research and consulting interests are focused on the styles and kinematics of salt tectonics, the processes of salt-sediment interaction, the architecture and evolution of passive margins, and the applications to petroleum exploration. He is the author or coauthor of over 80 papers and 170 abstracts, is the regular instructor for AAPG’s Salt Tectonics school, and has been an AAPG Distinguished Lecturer and an AAPG International Distinguished Instructor.

Steve Boyer

Steve Boyer, PhD

Associated Expert

Structural analysis and Tectonics, i.e. cross-section balancing, 3D geometry/ kinematic evolution of fold-thrust systems, implications for fluid flow and HC generation/ migration

Steve Boyer's Bio
Steve holds a PhD in structural geology from the Johns Hopkins University, where he studied under the late David Elliott. He also earned a BS in geology from Bucknell University under the late Richard Nickelsen. His undergraduate studies and doctoral dissertation exposed him to Appalachian and Alberta fold-&-thrust belt geology. Steve has 40 years of academic and exploration experience in compressional and extensional provinces. He was an exploration geologist in the Rocky Mountains for ARCO and SOHIO and was a thrust-belt development geologist with AMOCO. His industry experience also included work in the Basin and Range extensional province, Rocky Mountain foreland basement-involved terranes and seismic interpretation on the Alaskan North Slope. His interests have included cross-section balancing, the 3D geometry of fold-thrust systems, cross-section balancing and the kinematic evolution of thrust belts, including implications for fluid flow and hydrocarbon generation and migration. In the 1980s he helped Nick Woodward and John Suppe develop and teach a short course on cross-section construction and balancing. Currently he is interested in “sub-resolution” strain and implications for cross-section balancing. 

Sherilyn Williams-Stroud, PhD

Associated Expert

Fractured Reservoir Characterization; Microseismic, fracture modeling, structural restorations, reservoir stress/strain analysis, and rock fracture mechanics

Sherilyn Williams-Stroud's Bio
Sherilyn Williams-Stroud is a consulting geologist based in southern California. Her areas of expertise include fracture modeling, structural restoration, reservoir stress/strain analysis, and rock fracture mechanics with applications to oil and gas exploration and production in conventional and unconventional resources. She received her MA and PhD from The Johns Hopkins University and her BA from Oberlin College. Her more than 25 years of experience in government and industry includes research and technical support in the exploration and production technology departments of major oil companies, as well as providing consulting services to operators world-wide while employed at Midland Valley Exploration and MicroSeismic Inc. In addition to teaching industry short courses in her areas of expertise, she taught geology at the University of Houston while employed full time in the oil and gas industry and is a former full-time faculty of Whittier College. She has significant expertise interpreting and utilizing microseismic data, and is the co-author of a patented methodology to integrate microseismic data into geologic interpretations for fracture modeling of microseismic results for use in reservoir simulation.

Al Lacazette, PhD

Associated Expert

Fractured reservoir exploration, development, and simulation; reservoir-scale structural geology fluid-rock interaction; borehole imaging, hydraulic fracturing and Structural Geology

Alfred Lacazette's Bio
Alfred Lacazette received his PhD in Geoscience from Penn State, where he studied with Terry Engelder.  Al’s PhD work focused on natural hydraulic fracturing of tight gas sandstones and gas shales.  His PhD work resulted in publication (with Terry Engelder) of the first papers on the mechanics of natural hydraulic fracturing by poroelastic effects, which have become the basis for understanding catagenic fracturing in gas shales.  Al has worked for both operating companies and service companies in exploration, exploitation, and technology research & development roles.  His work and publications have focused on seismic-to-borehole-scale structural interpretation; fractured reservoir exploration, development, and simulation; the chemical and mechanical interplays of fluid-rock interaction; outcrop analog studies of fractured reservoirs; borehole imaging; and since 2008 the reservoir-scale structural geology of unconventional reservoirs and passive seismic imaging of induced and natural subsurface fracture networks.  Geological software development has also been a focus.  Among other projects, he wrote the technical specifications for the borehole image interpretation and orientation statistics packages of LR Senergy’s Interactive Petrophysics software.

Amy Fox, PhD

Associated Expert

Geomechanics, in situ stress determination and mapping, wellbore stability analysis, induced seismicity, fault stability, critically stressed fracture analysis

Amy Fox's Bio
Amy earned an undergraduate degree in Geology from the University of New Hampshire and a PhD in Geophysics from Stanford University. At Stanford she was part of Dr. Mark Zoback’s research group specializing in geomechanics. She has been involved in geomechanical consulting for the oil and gas industry since 1998, starting her career with GeoMechanics International (GMI) in Palo Alto, California. After Baker Hughes acquired GMI in 2008, Amy became a manager of technical training and development. In 2011 she returned to operations and moved from the U.S. to Canada. From 2012 to 2015 Amy started and directed a geomechanics consulting group for a small Canadian service company. Now she runs Enlighten Geoscience Ltd., addressing a variety of geomechanics issues for a wide range of clients. Amy has authored or co-authored many articles, given dozens of talks, volunteers for professional organizations and works hard to promote understanding and application of the geomechanics discipline.

Tanya Inks, MSc

Associated Expert

Seismic interpretation, processing QC; fractures, anisotropy and seismic attributes analysis, conventional and unconventional play analysis e.g. Marcellus Shales, Niobrara

Tanya Inks's Bio
Tanya Inks received B.S. and M.S. degrees in geophysical engineering from the Colorado School of Mines.  Since 1993, she has been providing integrated geophysical and geologic consulting services in Denver, Colorado.  Her recent projects have included work several unconventional plays including the Marcellus Shale play and the Niobrara play. She has been a partner in IS Interpretation Services, Inc. since 1998.  Previous experience included work as a consultant and manager for Vector Interpretation Services,  as an explorationist for Mobil Exploration and Producing US Inc, in the Rocky Mountain and Gulf of Mexico and, prior to graduate school, as a processor for Geophysical Service Inc., and CGG.  In addition to her work in the Appalachian and in the DJ Basin, she has contributed geoscientific expertise to exploration and field development projects in structurally and stratigraphically complex areas, such as the Bearpaw uplift and Disturbed Belt in Montana, The Greater Green River, Wind River and Big Horn Basins of Wyoming, Utah’s Uinta Basin, the North Slope of Alaska, California’s Sacramento and San Joaquin Basins, Oklahoma’s Arkoma Basin, as well as international projects in onshore Trinidad, Columbia’s thrust belt, Chile’s Fell Block and Venezuela’s thrust belt. She is a longtime member of the SEG, AAPG, DGS, and RMAG and has professional certification through the AAPG as a Certified Petroleum Geophysicist.

Afshin Fathi

Afshin, PhD

Associated Expert

Basin modeling, organic geochemistry, petroleum geology, exploration engineering

Afshin Fathi's Bio

Afshin is a basin modeler and organic geochemist with more than 15 years of experience. His educational background is in petroleum exploration, organic geochemistry and mining exploration. This provides him with great abilities to understand and solve HC exploration problems. During his journey in oil and gas industry, he developed new ideas and technologies which led to publishing several papers and two patents. Afshin worked for the Research Institute of Petroleum Industry (RIPI) as a product manager of Basin Modeling software development team for 8 years. He has experience in modeling several conventional and unconventional basins located in Europe and northern part of the Arabian plate.  During his career, he instructed lectures, presentations and on job training for different geological communities, companies and universities, including Polytechnic University of Tehran, Tehran University, National Iranian Oil Company, RIPI, POGC, Canada’s Energy Geoscientists. He is a member of AAPG, HGC, HOGC, SPE, and APPIH.

His research interests are: organic geochemistry, basin modeling, software development, applications of new mathematical and statistical methods in petroleum exploration, and unconventional resources exploration.

Margaret Lessenger, PhD 

Associated Expert

Unconventional resource petrophysics, integrated petrophysical data analytics, basin-scale high-resolution sequence stratigraphy, and sedimentology

Margaret A. Lessenger's Bio
Dr. Margaret A. Lessenger is a petrophysicist with over 30 years broad experience in petroleum geology, petrophysics and geophysics. She has a proven track record of solving difficult petroleum exploration and production problems using creative and innovative approaches based on sound scientific and engineering principles. Dr. Lessenger specializes in unconventional resource petrophysics, integrated petrophysical data analytics, basin-scale and high-resolution sequence stratigraphy, and sedimentology. She has worked for the Superior Oil Company, ARCO Oil and Gas, Platte River Associates, the Colorado School of Mines Department of Geology, Williams Exploration, and Newfield Exploration. Lessenger holds a BS in Geophysical Engineering, MS in Geophysics, and PhD in Geology from the Colorado School of Mines. She is a member of SPWLA, AAPG, SPE and SCA.

John Karlo, PhD 

Associated Expert

Structural Geology/Tectonics, Seal Evaluation, Salt Tectonics, Deep Water Exploration, Risk Assessment

John Karlo's Bio
John has a BA from Rutgers, an MA from Univ. Missouri and a Ph.D. in structure and tectonics from S.U.N.Y.  He taught structure and geophysics at Central Michigan University before joining industry.  He spent 30 years with Shell followed by 5 years with Maersk Oil and 2 years with Repsol. He has had positions in play development and prospect evaluation, regional teams, deepwater exploration, merger and acquisition and for 10 years was a senior advisor in Quality Assurance overseeing rigor in structural interpretation.  He has worked in rifts, passive margins, fold belts and turbidites in over 25 basins worldwide. Some of the high points in his career include the first regional synthesis of the Dutch North Sea tectonics, groundbreaking work on Gulf of Mexico salt tectonics and deepwater exploration leading to world class discoveries in Nigeria.  His current focus is on the complex subject of seal evaluation – how to risk seal and consider potential column height – which he sees as the weakest links in many exploration projects.

David Garner, MSc 

Associated Expert

Applied Geostatistics and Geomodeling, Multi-disciplinary Reservoir Characterization  

David Garner's Bio
David Garner has more than 30 years of technical experience in industry with over 20 years in applied geostatistical studies in petroleum and mining. He has published and presented over 25 papers, many of which were peer-reviewed. Currently, he is an applied geostatistician/geomodeler, trainer and an associate of Geovariances in Fontainebleau, France. Previously Mr. Garner held positions in Halliburton as a Chief Scientist in R&D, as a Specialist in Statoil’s Heavy Oil Technology Centre-Unconventionals R&D, as Senior Advisor Geologic Modeling for Chevron Canada Resources, and Reservoir Characterization Specialist at ConocoPhillips Canada. He was president of TerraMod Consulting for 6 years applying geostatistics and geomodeling techniques mainly for large international reservoir studies and mining resources. As a volunteer, Mr. Garner currently serves as a co-chair for the CSPG Geomodeling Technical Division committee and is chair/convener for the upcoming Gussow conference, Closing the Gap III Advances in Geomodeling for Petroleum Reservoirs to be held in October, 2018.  He was general chair for the CSPG 2011 and 2014 Gussow conferences, co-editor of the special edition December 2015 BCPG on Geomodeling Advances and the 2013 CSPG Memoir 20.  

Ursula Hammes, PhD 

Associated Expert

Sedimentology, stratigraphy, reservoir characterization, unconventional shale gas/oil analyses,  geochemistry

Ursula Hammes's Bio
Dr. Ursula Hammes obtained her Diploma in Geology from the University of Erlangen in Germany in 1987 and her PhD from the University of Colorado at Boulder in 1992. She spent ten years working as a consultant, performing postdoctoral research at the Bureau of Economic Geology, and as exploration geologist in industry. Dr. Hammes worked at the Bureau of Economic Geology and the University of Potsdam, Germany, as a Research Scientist and currently teaches at Texas A&M University as Halbouty Visiting Chair. Since January 2017, she has been consulting for a variety of oil and gas companies as well as teaching classes in evaluation of shale oil/gas plays.  Her main research focus is in shale-gas/oil systems specializing in basin to nano-scale characterization of shale basins. Other research interests and specialities include clastic and carbonate sequence stratigraphy, analyses of depositional systems, and carbonate and clastic diagenesis. She has published more than 200 papers, 400 abstracts, and served as AAPG Bulletin Editor, AAPG session chair, GCSSEPM President, and lecturer  

Peter Flaig, PhD 

Associated Expert

Fluvial-Deltaic-Shallow Marine Reservoir Characterization, 2D-3D High-resolution Image Capture and Analysis, Ichnology and Paleopedology

Peter Flaig's Bio
Dr. Flaig earned his BS and MS at the University of Wisconsin and his PhD at the University of Alaska. He is a clastic sedimentologist/stratigrapher specializing in outcrop to subsurface investigations of ancient fluvial, deltaic, and shallow marine depositional systems that act as petroleum reservoirs or serve as reservoir analogues. Dr. Flaig combines classic sedimentologic techniques with detailed ichnology, paleopedology, high-resolution image capture (GigaPan, drone photogrammetry, LiDAR), and core-sample analysis to identify depositional systems and provide industry with an estimate of facies and architectural element distribution. His research focus is identifying the relative controls on sedimentation style including tides, waves, river floods, discharge variability, accommodation, and fluctuating base level to predict sandbody-shale geometries, stratal stacking, and reservoir quality. He has led numerous industry field courses to outcrops of ancient paralic reservoir analogues in Utah, Colorado, Wyoming, New Mexico, and Alaska to examine heterogeneity and the lateral-vertical extent and distribution of reservoir and non-reservoir facies. He regularly runs core workshops and field courses, collaborates with experts in complimentary disciplines, and consults for industry on clastic or mixed carbonate-clastic systems.


Katie Joe McDonough, PhD 

Associated Expert

Sequence stratigraphy, stratigraphic basin analysis, exploration play

Katie Joe McDOnoughs's Bio
Katie-Joe McDonough, PhD., is a geological/geophysical consultant specializing in sequence stratigraphic and seismic interpretation. She began her career as a geophysicist with Exxon USA in Denver. As seismic stratigraphy burgeoned in the 80s, she turned to the Colorado School of Mines, earning her Ph.D. in 1997 working the seismic-scale carbonate outcrops in the Southern Alps. Her areas of expertise in sedimentology and depositional systems form the foundation of her work in stratigraphic basin analysis, exploration play assessment and reservoir-scale development. Dr. McDonough launched her consulting practice in 1995, and has enjoyed consulting/advisory/mentoring gigs working diverse, integrated data sets for the international and domestic U.S. petroleum industry for over 25 years. She works continental to deep marine strata in conventional and unconventional plays in North and South America, East/West Africa, Europe, Indonesia and the Arctic. She is an active member of AAPG (2015 & 2001 Annual Conference Technical Committees), DIPS, DGS, RMAG, SEPM-RMS and SEG. Dr. McDonough has also served as adjunct faculty teaching Stratigraphy at Colorado School of Mines, and currently serves as an industry mentor to RMAG YPs and to CSM graduate students in the Reservoir Characterization Project.


Alexei Mikov, PhD 

Associated Expert

Petroleum System Modeling, unconventional reservoirs, oil & gas geochemistry, exploration risk analysis, resource assessment, and portfolio analysis

Alexei Milkov's Bio
Dr. Alexei V. Milkov is Full Professor and
Director of Potential Gas Agency at Colorado
School of Mines and a consultant to oil and gas
industry. After receiving PhD from Texas A&M
University, Dr. Milkov worked for BP, Sasol and
Murphy Oil as geoscientist and senior manager.
He explored for conventional and
unconventional oil and gas in >30 basins on six
continents and participated in the discovery of
>4 Billion BOE of petroleum resources. He also
worked on several appraisal and production
projects. Dr. Milkov has deep expertise in oil
and gas geochemistry, petroleum systems
modeling, exploration risk analysis, resource
assessments and portfolio management. He
published ~50 peer-reviewed articles. Dr.
Milkov received several industry awards
including J.C. “Cam” Sproule Memorial Award
from the American Association of Petroleum
Geologists (AAPG) for the best contribution to
petroleum geology and Pieter Schenck Award
from the European Association of Organic
Geochemists (EAOG) for a major contribution
to organic geochemistry.

Tim Buddin, PhD 

Associated Expert

Structural modeling, restoration, geomechanical forward models, regional to reservoir, salt tectonics, thrust belts, extension and inversion

Tim Buddin's Bio
Dr. Tim Buddin is a quantitative structural geoscientist with 27 years post-Ph.D. experience including 10 years in BP, 8 years in smaller oil companies with diverse portfolios and scales of operation and 9 years in specialist consulting roles. He has structural interpretation and model building experience in all structural styles and across the scale range from plate scale to fracture characterization; including working complex mobile salt environments, thrust belts, strike slip environments, extensional & passive margin tectonics and inversion in over 40 basins/mountain belts across the globe.
A recurring theme has been the provision of multiple structurally viable interpretations in complex geology and the use of restoration and forward modeling to constrain interpretation ranges and ensure viable kinematic histories. He has always focused on fully integrating viable structural models into mainstream workflows from exploration through mature field reservoir modeling.
Recent projects have applied the rapidly advancing techniques for geomechanical multi-layer numerical modeling (using advanced constitutive models of failure & post-failure behaviour) to constrain strain histories (fault/fracture distribution, sub-seismic geometry) and understand the behaviour of natural fracture networks under hydraulic stimulation

Eric Scott, PhD 

Associated Expert

Petroleum Geologist, Sedimentology, Stratigraphy, Seismic Interpretation, HC Volumetric Assessment, Geologic Risking

Eric Scott's Bio
Erik received his Ph.D. in Sedimentology from Louisiana State University working with Dr. Arnold Bouma. He has over 25 years’ experience understanding petroleum systems working across the full life cycle of the industry; from regional geology, acreage evaluation, prospect maturation, discovery delineations, appraisal and development studies through to late field life recompletion evaluation and near field exploitation across six continents. He is a recognized industry expert in sedimentology, particularly in clastic depositional settings, and has expertise in the geologic analysis of seismic data and integrated petroleum systems evaluation. Erik is routinely called upon for peer reviews/assists evaluating all aspects of the petroleum system, volumetric inputs/calculations and geologic risk assessment for exploration, development and production projects. He is an active coach and mentor of all experience levels of technical staff through informal and formal settings and is a short course / workshop instructor and field trip leader.

Farrukh Ahmad, PhD 

Associated Expert

Seismic interpretation & attributes, Prospect maturation & risk assessment, Acreage & prospect evaluation, Coaching & Mentoring

Farrukh Ahmad's Bio
Farrukh currently a Geophysical Consultant with 44 years of oil & gas exploration and production experience that included working for Gulf, Texaco, Total and Maersk oil companies. He has >1.6 bboe discoveries to his credit with working worldwide in more than 15 basins. Dr. Ahmad worked in both exploration and production phases of the oil & gas industry and specializes in seismic interpretation, seismic attributes, AVO/AVA, prospect maturation & risk/reserves estimates, salt tectonics and subsalt mapping. He received his M.S. and Ph.D. from the University of Massachusetts, has more than 25 publications and major company reports, and has been heavily involved in SEG, GSH and OTC societies in many capacities. Dr. Ahmad was also very active in developing courses for companies, teaching them and mentoring young professionals.

“The flexible and focused services of TerraEx Group are exactly what our industry needs right now”

Hermann Lebit, PGS

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ACE 2020

January 8th, 2018|0 Comments

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