Evidence map›Paper›PMID 41798860›Full record

ArticleOpen research Europe2025

Investigative research for occurrences of hydrogen, helium, methane and carbon dioxide in West Macedonia: linking geological reservoirs to subsurface gas generation and migration.

Pavlos Tyrologou, Nikolaos Koukouzas, Nazaré Couto, Christos L Stergiou, Júlio Carneiro

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Article in Open research Europe, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Pavlos TyrologouChemical Process and Energy Resources Institute (CPERI), Centre for Research and Technology Hellas (CERTH), Marousi, Egialias 52, 151 25,, Greece.ORCID https://orcid.org/0000-0001-7706-1774
Nikolaos KoukouzasChemical Process and Energy Resources Institute (CPERI), Centre for Research and Technology Hellas (CERTH), Marousi, Egialias 52, 151 25,, Greece.
Nazaré CoutoCenter for Environmental and Sustainability Research & CHANGE - Global Change and Sustainability Institute, NOVA School of Science and Technology, NOVA University, Lisbon, Campus de Caparica, 2829-516 Caparica, Portugal.ORCID https://orcid.org/0000-0002-2911-6432
Christos L StergiouChemical Process and Energy Resources Institute (CPERI), Centre for Research and Technology Hellas (CERTH), Marousi, Egialias 52, 151 25,, Greece.ORCID https://orcid.org/0000-0003-2969-7262
Júlio CarneiroICT/IIFA, Geosciences Department, Universidade de Évora, Évora, R. Romão Ramalho, 7000-671, Portugal.ORCID https://orcid.org/0000-0002-4900-3355

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Exploration of subsurface gases such as hydrogen, helium, methane, and carbon dioxide can be achieved by integration of geological framework, hydrogeochemistry, and isotope analysis to understand generation, migration, and trapping mechanisms. A focused hydrogeochemical survey for the aforementioned gases was conducted in West Macedonia (Greece) to identify potentially suitable locations for geological reservoirs, gas sources and gas migration routes based on previous research. West Macedonia (Greece) is characterised by ophiolitic complexes, sedimentary basins, and active fault systems. This presents favourable geological conditions for investigating potential gas reservoirs and migration pathways. Methods: The investigation presented in this study deployed sequential spring and borehole water sampling for geochemical analysis of trace elements and gas analysis for hydrogen, helium, methane and carbon dioxide to identify and characterise gaseous geological reservoirs. The investigation extended into isotope studies for d Results: The analysis provided evidence for the existence of helium, biogenic methane, carbon dioxide and traces of hydrogen that need to be further investigated for validation and better understanding of the gas generation and migration routes. Variations in dissolved ions and gas composition largely reflect enrichment of resident groundwater by meteoric recharge and subsequent water-rock interaction. Fault-controlled pathways appear to facilitate multi-gas signatures in specific locations. Conclusions: The data suggests the existence of helium, methane, carbon dioxide and validated trace concentrations of hydrogen from previous studies in the wider area. Isotopic analysis provides strong evidence for biotic generation of methane, whereas helium comes from a deeper source. Hydrogeochemical controls, structural features, and lithological variability collectively influence gas occurrence. This preliminary investigation indicates the existence of multiple gas generation and migration mechanisms and provides a scientific basis for further targeted exploration of natural hydrogen and associated gases.

Indexed as

gas migrationgeological reservoirsgeological storageheliumisotopemethanenatural hydrogen

Identifiers

PMID41798860
PMCPMC12963835

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