The deep subsurface biosphere is the largest microbiological habitat on Earth, with biomass and contributions to biogeochemical cycles comparable to the surface biosphere. Deciphering the parameters that control and sustain deep subsurface life is vital in understanding how our planet functions, and additionally provides key information on how life emerged and where it could exist elsewhere. Among these parameters are the sources of essential energy for deep life, such as hydrogen gas (H2) and methane (CH4). Great effort has been made to identify geological processes producing these compounds within the subsurface biosphere. Conversely, the identification of deeper sources of H2 and CH4 produced outside the parameter space for life is lacking, even though they could dramatically change our understanding of the distribution and magnitude of deep life on Earth and potentially beyond.
Convergent margins focus the largest recycling of carbon from the deep Earth to the biosphere and atmosphere. Current models of deep carbon cycling do not include deep fluxes of H2-CH4 and therefore cannot assess their potential role in sustaining deep life. Our recent work indicates that H2 and CH4 can be produced in large amounts abiotically (without bioloigcal involvement) in subduction zones well below the biosphere by high-pressure serpentinization processes. This opens new fundamental questions: What is the magnitude of deep H2 and CH4 production at convergent margins? How do they affect deep carbon cycling? To what extent do deep H2 and CH4 fluxes sustain the biosphere?
ERC DeepSeep (Grant No. 864045) will answer these questions by providing the first ever estimates of deep H2-CH4 fluxes, as well as provide means, absent from our current scientific understanding, to detect source areas at depth. We will therefore establish what the role of deep H2-CH4 generation is on deep carbon cycling and deep biosphere processes. By bridging the two most contrasting peculiarities of Earth, tectonic subduction and life, ERC DeepSeep has the potential for transformative discoveries, with long-term implications for global carbon cycle modeling, climatology, and the emergence and search for life on Earth and beyond.
Publications
Here is a list of ERC DeepSeep-funded publications resulting from research at the Deep Carbon Lab, University of Bologna, from 2021 onwards. Currently affiliated Deep Carbon Lab researchers are included in bold.
2025
Forms and fluxes of carbon: Surface to deep
Alberto Vitale Brovarone, Kevin Wong, Donato Giovannelli, Benoit de Pins, Fabrice Gaillard, Malcolm Massuyeau, Fabrizio Nestola, Martha Giovanna Pamato, and Isabelle Daniel
Treatise on Geochemistry (3rd Edition) Volume 2, 647–698 (2025), doi.org/10.1016/B978-0-323-99762-1.00142-X
2024
Protocols for bulk off-line fluid inclusion extraction for the analysis of δ13C-CH4 and δ13C-CO2 using a cavity ring-down spectroscopy (CDRS) analyser
Frontiers in Earth Science 12 (2024), doi.org/10.3389/feart.2024.1438382 (open access)
Cold-subduction biogeodynamics boosts deep energy delivery to the forearc
Veronica Peverelli, Orlando Sébastien Olivieri, Tatsuki Tsujimori, Donato Giovannelli, Guanghai Shi, Enrico Cannaò, Francesca Piccoli, and Alberto Vitale Brovarone
Geochimica et Cosmochimica Acta (2024), doi.org/10.1016/j.gca.2024.10.004 (open access)
Behaviour of fluid-mobile elements across a high-pressure serpentinization front (Monte Maggiore unit, Alpine Corsica)
Francesco Ressico, Enrico Cannaò, Orlando Sébastien Olivieri, Zeudia Pastore, Veronica Peverelli, Nadia Malaspina, and Alberto Vitale Brovarone
Chemical Geology 662 (2024), doi.org/10.1016/j.chemgeo.2024.122228
Lawsonite and Garnet Oxygen Isotope Record of Fluid-Rock Interaction During Subduction
Patricia Kang, Laure A. J. Martin, Alberto Vitale Brovarone, and Donna L. Whitney
Geochemistry, Geophysics, Geosystems 25 (2024), doi.org/10.1029/2023GC011389 (open access)
Reaction path model of the formation of abiotic immiscible hydrocarbon fluids in subducted carbonated serpentinites, Lanzo Massif (Western Italian Alps)
Jingyi Huang, Dimitri A Sverjensky, Isabelle Daniel, and Alberto Vitale Brovarone
Lithos 468 (2024), doi.org/10.1016/j.lithos.2024.107498
Thermotopes-COH—A software for carbon isotope modelling and speciation of COH fluids
Computers & Geosciences 184 (2024), doi.org/10.1016/j.cageo.2024.105533
Methane-hydrogen-rich fluid migration may trigger seismic failure in subduction zones at forearc depths
Francesco Giuntoli, Luca Menegon, Guillaume Siron, Flavio Cognigni, Huges Leroux, Roberto Compagnoni, Marco Rossi, and Alberto Vitale Brovarone
Nature Communications 15 (2024), doi.org/10.1038/s41467-023-44641-w (open access)
Complexity of graphite formation in response to metamorphic methane generation and transformation in an orogenic ultramafic body
Antoine Boutier, Isabelle Martinez, Olivier Sissmann, Samuele Agostini, Isabelle Daniel, Mark Van Baalen, Sara Mana, and Alberto Vitale Brovarone
Geochimica et Cosmochimica Acta 364 (2024), doi.org/10.1016/j.gca.2023.10.028 (open access)
2023
Global Hydrogen Production During High‐Pressure Serpentinization of Subducting Slabs
Andrew S. Merdith, Isabelle Daniel, Dimitri Sverjensky, Muriel Andreani, Ben Mather, Simon Williams, and Alberto Vitale Brovarone
Geochemistry, Geophysics, Geosystems 24 (2023), doi.org/10.1029/2023GC010947 (open access)
Ti-bearing minerals: from the ocean floor to subduction and back
Inês Pereira, Emilie Bruand, Christian Nicollet, Kenneth T. Koga, and Alberto Vitale Brovarone
Journal of Petrology 64 (2023), doi.org/10.1093/petrology/egad041 (open access)
Coupled surface to deep Earth processes: Perspectives from TOPO-EUROPE with an emphasis on climate-and energy-related societal challenges
Sierd Cloetingh, Pietro Sternai, Alexander Koptev, Todd A. Ehlers, Taras Gerya, István Kovács, Johannes Oerlemans, Fred Beekman, Yan Lavallée, Donald Dingwell, Eszter Békési, Kristóf Porkolàb, Magdala Tesauro, Alessio Lavecchia, Svetlana Botsyun, Veleda Muller, François Roure, Enrico Serpelloni, Liviu Matenco, Sébastien Castelltort, Donato Giovannelli, Alberto Vitale Brovarone, Nadia Malaspina, Giovanni Coletti, Pierre Valla, and Jon Limberger
Global and Planetary Change 226 (2023), doi.org/10.1016/j.gloplacha.2023.104140 (open access)
Dating fluid infiltration and deformation in the subducted ultramafic oceanic lithosphere by perovskite geochronology
Francesca Piccoli, Daniela Rubatto, Maria Ovtcharova, Jörg Hermann, Marcel Guillong, and Alberto Vitale Brovarone
Chemical Geology 615 (2023), doi.org/10.1016/j.chemgeo.2022.121205 (open access)
2022
An Experimental Study on Kinetics-Controlled Ca-Carbonate Aqueous Reduction into CH4 (1 and 2 GPa, 550°C): Implications for C Mobility in Subduction Zones
Weigang Peng, Simone Tumiati, Lifei Zhang, Carla Tiraboschi, Alberto Vitale Brovarone, Luca Toffolo, and Stefano Poli
Journal of Petrology 63 (2022), doi.org/10.1093/petrology/egac070
Subducted organic matter buffered by marine carbonate rules the carbon isotopic signature of arc emissions
Simone Tumiati, Sandro Recchia, Laurent Remusat, Carla Tiraboschi, Dimitri A. Sverjensky, Craig E. Manning, Alberto Vitale Brovarone, Antoine Boutier, Davide Spanu, and Stefano Poli
Nature Communications 13 (2022), doi.org/10.1038/s41467-022-30421-5 (open access)
2021
In-situ abiogenic methane synthesis from diamond and graphite under geologically relevant conditions
Miriam Peña-Alvarez, Alberto Vitale Brovarone, Mary-Ellen Donnelly, Mengnan Wang, Philip Dalladay-Simpson, Ross Howie, and Eugene Gregoryanz
Nature Communications 12 (2021), doi.org/10.1038/s41467-021-26664-3 (open access)
Abiotic methane generation through reduction of serpentinite-hosted dolomite: implications for carbon mobility in subduction zones
Weigang Peng, Lifei Zhang, Simone Tumiati, Alberto Vitale Brovarone, Han Hu, Yachun Cai, and Tingting Shen
Geochimica et Cosmochimica Acta 311 (2021), doi.org/10.1016/j.gca.2021.07.033