Contact Information

  • Mark Tomasso


Geoscientist with 20 years’ experience in the integration of diverse geological and geophysical datasets to undertake petroleum systems analyses, developing robust regional- to block-level interpretations and defining conventional and unconventional exploration prospects.  My experience covers frontier exploration, new ventures analyses and reviews, and exploitation of legacy producing fields.  This had been undertaken both onshore and offshore, including activity around the Atlantic Margin (Suriname/Guyana, Gulf of Guinea, Mauritania/Senegal, Ireland, and Brazil), US onshore, New Zealand, and the North Sea. 

I have a versatile functional experience set, including tectonostratigraphic analysis from well, seismic and other remote sensing data, seismic mapping and attribute analysis, GDE development, basin modeling, and lead and prospect development with associated volumetric and risk assessment.  I have participated in the planning and drilling of multiple offshore and onshore wells in exploration, appraisal, exploitation and development scenarios.  I am a recognized expert in structurally complex deep-water systems, with experience in depositional environments including carbonates.

I am a dynamic self-starter, able to adjust quickly to new geographic areas.  I work effectively in a cross-functional team environment, having extensive experience in collaborative inter-company and JIP projects.  I am an effective, experienced presenter to various audiences from team, to partner, to Ministerial level, and have an intermediate fluency in French.  I am also licensed as a Professional Geologist by the states of Texas and Wyoming.


Dallas; open to relocation


Kosmos Energy LLC, Dallas, Texas, 7/13 – 11/20
Senior Exploration Geologist & Technical Team Lead
• Technical Team Lead, Suriname (2017-2020): Oversaw exploration geoscience activity over two operated licenses, as well as regional integration. Development of a multi-billion barrel lead-to-prospect pipeline and exploration well drilling. Mapping, GDE generation, AVO integration, basin modelling, deterministic/probabilistic volumetric calculations, prospect risking and post-well analysis. Exploration geologist on two exploration wells in the region. Team guidance and leadership, including internal, partner and governmental coordination and reviews.
• Technical Team Lead, São Tomé & Príncipe and Equatorial Guinea (2020): Exploration oversight and analysis of three operated and three non-operated frontier exploration licenses in STP and EG.
• New Ventures (2013-2020): Participate in new venture analyses and recommendations for potential access in multiple countries around the Atlantic Margin.
• Exploration geologist, Mauritania and Senegal (2015-2017): Part of small exploration team unravelling the multi-TCF Cretaceous outboard gas trend opened-up by Kosmos. Regional characterization of the MSGBC Basin, including sediment provenance prediction, seismic mapping, hydrocarbon phase prediction through basin modeling, prospect generation, AVO integration, and volumetric assessment. Exploration geoscientist on drilling and post-well analysis of two gas discovery and appraisal wells in Senegal and Mauritania. Lead on development of the initial appraisal programs for two significant gas discoveries in Senegal and Mauritania.
• Exploration geologist, Ireland (2013-2015): Characterization of the Porcupine Basin, Irish Atlantic Margin. Developed and tested stratigraphic and provenance concepts, generate regional GDEs, and regional to prospect-level 2D and 3D seismic interpretation. Lead and prospect identification, mapping, analysis, and calculation of associated volumetrics across three operated frontier exploration licenses.

Merit Energy Co., Dallas, Texas, 1/11 – 7/13
Senior Geologist
• Multiple function role: Development, drilling operations, and exploration geology and geophysics, plus support for acquisitions and divestitures.
• Lead geologist for the Rockies region, focusing on Wyoming: Regional to intra-field stratigraphic and structural characterization of fields and reservoirs, integrating various data to identify development opportunities through additional wells, field conformance projects, or exploitation of behind-pipe pay. Calculation of reservoir volumes for OOIP estimation. In-field and exploration well siting and drilling.
• Lead geomodeler: Initiated Merit’s in-house 3D geological modeling capability, resulting in identifying additional intra-field drill prospects in highly exploited reservoirs.
• Additional exploitation and drilling experience: South central Oklahoma, including the Woodford Shale.

Principal/consultant, various locations, 1/01 – 1/11
• Consulting with national/international oil and gas companies. Prospect evaluation and near-field/lease offset development analysis in both conventional and unconventional play regimes, including the Niobrara Shale. Seismic interpretation and characterization, plus application of outcrop analogs to the subsurface.

Enhanced Oil Recovery Institute, Laramie, Wyoming, 10/07 – 1/11
Senior Research Scientist
• Team lead, reservoir characterization: Working with companies to assess hydrocarbon reservoirs for potential upside. Integration of regional geological, geophysical and engineering data to develop robust static geological and reservoir models for OOIP estimates, and input into flow simulators. Used to recommend in-field drilling opportunities and EOR optionality.
• Team lead, outcrop characterization: Field data collection for characterization of clastic reservoir analogs. Development of 3D reservoir models and forward seismic models.

Bureau of Economic Geology, The University of Texas at Austin, Austin, Texas, 11/04 – 9/07
Research Associate
• Co-lead, technical collaboration with a national oil company (2007): Integration of seismic and well data (including wireline log and core) for interpretation of pre- and post-salt Cretaceous carbonate and clastic reservoirs, Campos Basin, offshore Brazil. Stratigraphic and structural interpretation, core logging, geological modeling and reservoir/play prediction. New models for exploration strategy, structure, salt tectonics, and carbonate deposition for the study area were developed. Teaching of best-practice techniques and mentoring of NOC staff.
• Principal investigator and geologist, technical collaboration with two partner companies (2005-2007): Investigating rock-property information from multicomponent seismic data for an incised valley reservoir target. Integration of seismic and well data to build a high-resolution reservoir model for forward seismic modeling using advanced wave-equation techniques.
• Stratigrapher and geological/seismic forward modeler, project LASR (Laser-assisted Analogs of Siliciclastic Reservoirs) (2004-2007): Industry-funded research project (nine companies). Detailed characterization of deep-water and fluvio-deltaic outcrops analogs for application to the subsurface. Development of 3D reservoir models and forward seismic modeling. Additional core logging of Miocene turbidites, offshore West Africa. Co-PI in 2006-2007; PI in 2007.
• Geologist, project FRST (Fluid-Rock-Seismic Technology) (2004-2005): Industry-funded collaborative research project with a major international oil company. Included stratigraphic and sedimentological analysis, generation of synthetic reservoir models, and forward seismic modeling techniques for prediction of reservoir properties in submarine channels.

Department of Geology, University College Dublin, Ireland, 10/02 – 10/04
Postdoctoral Research Fellow
• Stratigrapher and sedimentologist, project FIFT (Flow In Faulted Turbidites): Industry-funded (nine companies) research project examining the effects of faulting on hydrocarbon flow through turbidite systems. Analysis of a submarine-fan complex, from distributary canyons to basin-floor fans. Construction of generic turbidite models for flow simulation. Seismic analysis of tectonically-complex deep-water reservoirs and extensive field data collection in the slope to basin-floor deposits of the Mt. Messenger Formation of New Zealand.

Department of Geology, The University of Edinburgh, UK, 11/00 – 10/02
TotalFinaElf Postdoctoral Research Fellow
• Stratigraphic/sedimentological lead: A collaborative research study with a major oil company on the tectonostratigraphic evolution of the Triassic of the Northern North Sea, offshore Scotland and Norway. Integration of 3D and 2D seismic data, well log data, core, and field analog data to perform both regional analyses and assessment of near-field prospectivity.

Awards and Certifications

• Licensed Professional Geologist, State of Wyoming PG-3734


• Development of lead to prospect pipelines, with associated volumetric analysis and risking
• Able to quickly integrate large volumes of data to form robust petroleum systems analyses
• Seismic interpretation and analysis, including attributes, AVO, inversion and gather analysis
• Tectono-stratigraphic analysis in all depositional and structural environments
• Basin-scale to local GDE development
• Collaborates effectively in cross-functional teams including geologists, geophysicists, engineers, drillers, and BD
• Experience of static reservoir model building
• Current software experience includes Petrel, Trinity, Paleoscan, Geoteric, Hampson Russell Suite, Kingdom, Neuralog and ArcGIS. Experience with most other industry-standard software including Sismage, Petra and GoCAD


• Ph.D., Earth Sciences: The University of Birmingham, UK
• Master of Energy Business: The University of Tulsa
• B.Sc. (Hons), Geology: Royal Holloway, University of London, UK