b'FeatureHydrogen explorationpresence of shallow (10 km) mantle rocks overlaid by multipleReferencesdoleritic sills and aquifers (Lefeuvre etal. 2021), or subsurface salt structures (Andersson and Grnkvist 2019) Andersson, J and S Grnkvist, 2019 Large-scale storage of hydrogen Int. J. Hydrogen Energy 44, 1190111919 The storage of gaseous hydrogen in salt caverns is already useddoi:10.1016/j.ijhydene.2019.03.063on an industrial scale (Andersson and Grnkvist, 2019) As isAuzende, J. M. et al., 2000. Deep sea diapirs and bottom well known, salt deposition occurs as water evaporates andsimulating reflector in Fairway Basin (SW Pacific). thick accumulations characterise salt basins across the worldMarine Geophysical Researches, 21(6), 579587. Subsurface salt bodies may be significant in size and be 10- doi:10.1023/A:1004848715044.100s km long and several km high Hence, it is possible that saltDeville, E., Paita, G., Jeanpert, J., Sissman, O. and I. Moretti, 2021. bodies within the vicinity of buried mafic rocks may be chargedCharacteristics and distribution of H2-rich gas seepages in by hydrogen produced by serpentinisation and delivered byNew- Caledonia. Lhydrogne Nat. tat la Rech. en Fr. Socit faults (Figure 1) It is exciting that the geological and stratigraphicGologique Fr. 2021. Available at: https://www.geosoc.fr/accumulation of hydrogen, ie trap, may be achieved by theliens-docman/reunions-scientifiques-et-techniques/2021-presence of shallow ( 10 km) mantle rocks overlaid by multiple2/l-hydrogene-naturel-etat-de-la-recherche-en-france/1537-doleritic sills and aquifers (Lefeuvre et al., 2021), or subsurface saltcharacteristics-and-distribution-of-h2-rich-gas-seepages-in-structures (Andersson and Grnkvist, 2019) new-caledonia/file.html.Clearly, more research is required to improve our understandingDugamin, E., Truche, L. and F.V. Donz, 2019. Natural Hydrogen of how hydrogen migrates through the subsurface andExploration Guide. Geonum, 1, 16. Available at: https://whether recent generation coupled with short-term migrationwww.researchgate.net/publication/330728855_Natural_(compared to geological time scales) can deliver commerciallyHydrogen_Exploration_Guideexploitable hydrogen resources Recent estimates of velocitiesEllouz, N., Patriat, M., Gaulier, J. M., Bouatmani, R. and S. in generalised sandstones calculated using oil- and gas-waterSabounji, 2003. From rifting to Alpine inversion: Mesooic saturation relationships indicate that hydrogen may moveand Cenozoic subsidence history of some Moroccan vertically at ~4 m/year at the surface and ~2 m/year at a depthbasins. Sediment. Geol. 156, 185212. doi: 10.1016/S0037-of 2 km (Lodhia and Clark, 2022) Whilst these values are a0738(02)00288-9gross simplification, they illustrate the potential timescalesLefeuvre, N. etal., 2021. Native H2 Exploration in the Western of hydrogen migration Future research should focus onPyrenean Foothills. Geochemistry, Geophys. Geosystems 22, understanding hydrogen gas-water saturation relationships120. doi: 10.1029/2021GC009917Application to mafic and other rock properties may helpLodhia, B.H., and S.R. Clark, 2022. Computation of vertical fluid determine the migration pathways of hydrogen using a similarmobility of CO 2 , methane, hydrogen and hydrocarbons approach to Lodhia and Clark (2022) through sandstones and carbonates. Sci Rep 12, 10216. https://doi.org/10.1038/s41598-022-14234-6Even though naturally occurring hydrogen is found at surfacePatriat, M. etal., 2022. Mantellic Ophiolite of the SW Pacific: A seeps and within the subsurface, there exists no framework toNatural Hydrogen Potential to be Explored, Notably Offshore. explore for naturally occurring hydrogen in H 2 -rich geologicalPerspectives from New Caledonias Peridotite Nappe. In settings Momentum behind hydrogen exploration is growing,Structural Geology and Our Future: The Role of Tectonic with jurisdictions such as South Australia granting or receivingGeoscience in Energy Transition, Focusing on the Asia-Pacific applications for 18 exploration licenses by six differentRegion. American Association of Petroleum Geologists.companies searching for natural hydrogen since FebruaryPeacock, B., 2022. Natural hydrogen exploration boom snaps 2021 (Lodhia and Clark, 2022, Peacock, 2022) I believe thatup one third of South Australia. pv magazine Australia https://future research should focus on the development of a set ofwww.pv-magazine.com/2022/02/02/natural-hydrogen-standard criteria for hydrogen exploration, eg, presence ofexploration-boom-snaps-up-one-third-of-south-australia/serpentinised mafic rocks, migration pathways and existenceUlrich, M. et al., 2020. Serpentinization of New Caledonia of a storage medium Such criteria may hopefully contributeperidotites: from depth to (sub-)surface. Contributions to to the development of the concept of a hydrogen kitchen andMineralogy and Petrology, 175(9), 125. doi: 10.1007/s00410-commercial hydrogen exploration 020-01713-0The ASEG in social mediaHave you liked/followed/subscribed to our social media channels? We regularly share relevant geoscience articles, events, opportunities and lots more. Subscribe to our Youtube channel for recorded webinars and other content. Email our Communications Chair Millicent Crowe at communications@aseg.org.au for suggestions for our social media channels.Facebook: https://www.facebook.com/AustralianSocietyOfExplorationGeophysicistsLinkedIn company page: https://www.linkedin.com/company/australian-society-of-exploration-geophysicists/Twitter: https://twitter.com/ASEG_newsYouTube: https://www.youtube.com/channel/UCNvsVEu1pVw_BdYOyi2avLgInstagram: https://www.instagram.com/aseg_news/ OCTOBER 2022 PREVIEW 40'