Brian Horsfield Managing Director and CEO Brian Horsfield Managing Director and CEO Close Brian Horsfield is co-founder of GEOS4, and CEO. He graduated in Geology from Durham University (U.K.) and obtained his Ph.D in Organic Geochemistry from Newcastle University (U.K.). He has forty-five years of experience in Earth System research and development, beginning with Conoco and Arco exploration research in the seventies and eighties, followed by directorships in deep organic carbon cycles at Helmholtz institutions in Germany. Brian is an elected member of acatech, the German Academy of Science and Technology. He is Emeritus Professor of Organic Geochemistry and Hydrocarbon Systems at the Technical University of Berlin, Germany, and is Senior Scientific Advisor to the GFZ German Research Centre for Geosciences, Potsdam, Germany. His research interests include quantifying fractionation associated with natural migration and oil production, developing new kinetics models of petroleum generation and most recently quantifying natural organic hydrogen formation in time and space. He has about 300 publications to his name. His published papers include developing evaluation schemes that are now standard in the industry. Contact Selected Publications
Nicolaj Mahlstedt Senior Technical Officer Nicolaj Mahlstedt Senior Technical Officer Close Nicolaj Mahlstedt joined GEOS4 in 2013 as Petroleum System Analyst and is active as a guest scientist in the Organic Geochemistry group at GFZ German Research Centre for Geosciences, Potsdam, Germany. He graduated in Applied Geosciences and holds a Ph.D. from the Technical University of Berlin. He has 15+ years’ experience in upstream research and development with a focus on deep organic carbon cycling. Nick is a member of EAOG and AAPG. Nick´s major scientific interests include petroleum system analysis in sedimentary basins worldwide, generation of oil and energy gases (including H2) from organic matter, fractionation processes associated with natural oil migration/expulsion and production, compositional kinetic modelling for predicting phase behavior, and the development of geochemical screening tools/proxies. He published about 50 papers, many of them with direct impact for the work of GEOS4. Contact Selected Publications
Alex Hartwig Partner Risk and Play Performance Alex Hartwig Partner Risk and Play Performance Close Alex Hartwig studied exploration geology at the Technical University in Berlin. His master thesis in 2009 was the first peer-reviewed article on the shale-play potential of Northeast German source rocks. He attained his PhD from TU-Berlin on the topic of “Hydrocarbon migration and leakage in the Orange Basin, South Africa'' while working as PhD-researcher at the German Research Center for Geosciences (GFZ). In 2012 he began working as petroleum system analyst in ConocoPhillips’ (COP) L48 New Ventures Exploration in Houston, Texas. There he supported unconventional tight-oil and gas exploration and appraisal projects in all major US onshore basins. After a short period in COPs’ International New Ventures team, Alex accepted a position as petroleum system analyst with Aker BP and moved to Norway in 2016. At Aker BP, he worked in specialist and project-lead roles for exploration, digitization and R&D projects throughout the Norwegian Continental Shelf. From 2020 – 2023, he was the exploration manager for Aker BP’s New Ventures team, supervising regional project and R&D studies, developing and capturing new play concepts, as well as leading the annual application rounds for new exploration licenses offshore Norway. He works as an independent exploration consultant since October 2023. Alex focuses on assessing the subsurface risks for petroleum exploration and is interested in applying proven exploration workflows to geothermal, natural hydrogen and other critical energy resources. His research interests cover basin evolution, fluid migration, alteration and trapping mechanisms. Contact Selected Publications
David Misch Partner Organic Petrology and SEM David Misch Partner Organic Petrology and SEM Close David Misch obtained his PhD from Montanuniversitaet Leoben in 2016. His PhD thesis addresses "Conventional and unconventional petroleum systems in the Ukrainian Dnieper-Donets Basin." His postdoctoral research focused on the development and application of new in-situ analytical tools in shale geology, emphasizing the role of organic matter in porosity evolution during diagenesis. His further expertise includes basin analysis, organic petrography, and reservoir geology. In 2017, he worked as a postdoctoral fellow at the Department of Structural Geology, Tectonics and Geomechanics (GED) at RWTH Aachen University. In 2023, he was appointed Professor of Energy Geosciences at Montanuniversitaet Leoben, focusing on low-carbon geoenergy fields including geothermal energy recovery, aquifer thermal energy storage (ATES), natural hydrogen, underground hydrogen storage (UHS), and carbon capture and storage (CCS). Contact Selected Publications
Victoria Sachse Consultant Basin Modeller Victoria Sachse Consultant Basin Modeller Close Victoria Sachse joined GEOS4 in 2012 as Consultant Basin Modeller. Currently she works also as Senior Researcher at the Institute of Geology and Geochemistry of Petroleum and Coal, RWTH Aachen University, Germany. Victoria studied Geosciences at RWTH Aachen University where she obtained her Ph.D. dealing with the characterisation of petroleum source rocks and their relation to basin evolution. She was a Postdoc at GFZ German Research Centre for Geoscience, Potsdam, Germany, where she worked on her favourite scientific topics, including sedimentary basins dynamics, organic geochemistry, petrology, kinetics of hydrocarbon systems, and petroleum system/basin modelling. Contact Selected Publications
Shengyu Yang Consultant Biosignatures Shengyu Yang Consultant Biosignatures Close Shengyu Yang received his Ph.D. in organic geochemistry from the Technical University of Berlin in 2017, then spent two years as postdoc at the German Research Centre for Geosciences (GFZ) before joining China University of Petroleum (East China) as an Associate Professor. He is now full Professor of Petroleum Exploration (since 2022), having won a prestigious national award in China. He has published papers in Geology, GCA, and AAPG Bulletin etc, and currently serves as Associate Editor for AAPG Bulletin and Marine and Petroleum Geology. Shengyu’s expertise in MSSV-Hy-based bound biomarker analysis is his main link to GEOS4, though his background in petroleum geoscience is more diverse, encompassing exploration and production studies, and utilising pyrolytic, nanopetrophysical, and high-resolution GC techniques. Contact Selected Publications
Andreas Hübner Consultant Senior Enabler Andreas Hübner Consultant Senior Enabler Close Andreas Hübner joined GEOS4 in 2013 as Marketing Manager. He studied Geology at the Freie Universität Berlin, Germany, and the University of Edinburgh, UK, and completed a research internship at the Geological and Nuclear Service (GNS) in New Zealand. He holds a Ph.D. in Geochemistry from the Freie Universität Berlin, Germany, and worked as postdoc at the University of Utrecht, The Netherlands. Before joining GFZ German Research Centre for Geosciences, Potsdam, Germany, in 2006, he attended courses in environmental education management and science communication at Rostock University, Germany. During his time at GFZ he worked at the interface of research and communication in a variety of positions, covering topics like Open Access Publications, geological CO2 storage and, from 2011 to 2013, shale gas. With respect to the latter he was coordinator of the Shale Gas Information Platform SHIP, a network and communication tool for unbiased and science-based information on shale gas. Contact
