GEMANFLOW
Exploring the 3D dynamics of toroidal-poloidal mantle flow, geothermal network,
and intraplate submarine volcanism
PI: E. Attias (UTIG)
Collaborators: L. Lavier (JSG), M. K. Sen (JSG), M. Agius (University of Malta), Emma Chambers (Dublin Institute for Advanced Studies), Max Moorkamp (Technische Universität Berlin), Francesca Funiciello (Rome Tre University), S. Hölz (GEOMAR), F. Roth (EMGS)
GEMANFLOW is a multidisciplinary geophysical and geodynamic project designed to resolve how slab rollback–driven 3D mantle flow controls continental breakup, geothermal circulation, and submarine volcanism at the Sicily Channel Rift Zone (SCRZ). The SCRZ represents a rare end member of rifting at a convergent margin, where toroidal and potentially poloidal mantle flow (TPMF) associated with the Calabrian subduction system drives lithospheric thinning, nascent microplate formation, focused heat and volatile transport, and episodic intraplate volcanic activity, rather than plume-driven extension. This project integrates magnetotelluric (MT), marine electromagnetic (EM), controlled-source EM (CSEM) and ocean-bottom seismometer (OBS) observations with joint three-dimensional seismic–EM tomography and geodynamic modelling to image mantle flow patterns, lithospheric structure, and interconnected geothermal networks from the upper mantle to the seafloor and coastal Sicily. By coupling new and legacy datasets with petrological, geochemical, oceanographic, and biological constraints, the project quantifies how mantle viscosity, melt, temperature, and anisotropy regulate the upward focusing of heat and fluids that sustain submarine volcanism, geothermal systems, and potentially serpentinization-driven natural hydrogen accumulations. Beyond advancing fundamental understanding of subduction-driven continental breakup, GEMANFLOW establishes a transferable observational and modelling framework to characterise mantle flow–controlled geothermal networks and associated geohazards, including volcanic hazards to subsea infrastructure. The project directly links deep Earth dynamics to surface expressions relevant to clean energy exploration and humanitarian geophysics, while providing benchmark 3D models of mantle flow, rheology, and fluid transport applicable to other tectonically complex convergent rift systems worldwide.
What do we know about SCRZ from existing shallow datasets?
Evidence for crustal dynamics from intraplate and subduction-related volcanism (Faccenna et al., 2005), compression/extension (Devoti et al., 2011; Bahrouni et al., 2020), heat flow (Fuchs et al., 2021), seismic azimuthal/radial anisotropy and crustal thickness (Agius et al., 2022).
What do we know about SCRZ from existing deep datasets?
Evidence for upper mantle flow due to dynamic slab. Shear velocity structure at 100~km depth adopted from El-Sharkawy et al., (2020), shear-wave splitting from Barruol et al., (2009), and seismic surface-wave radial and azimuthal anisotropy data from Agius et al., (2022).
GEMANFLOW
GEMANFLOW seeks to establish a feasible workflow to map, constrain, and characterize the dynamics of interconnected amphibious geothermal networks that control submarine intraplate volcanism. The experiment has two main objectives: (1) Mapping SCRZ’s geothermal network to support the global effort in transitioning from carbon-prominent to carbon-low clean energies, in line with the 2015 Paris Agreement and the New Blue Economy initiative, and (2) Constraining the structural features and geodynamic processes that drive upward migration of traversing 3D mantle flow, which channels melt, heat, and volatiles to SCRZ submarine volcanoes—a geohazard that could potentially threaten communication and gas lines. Using an integrated approach, GEMANFLOW aims to improve our understanding of dynamically complex tectonic processes.
GEMANFLOW's methodologies include marine CSEM for mapping subsurface electrical resistivity, magnetic delineating tectonic features, biogeochemistry, heat flow, and oceanographic measurements to detect changes in the water column influenced by active submarine volcanism. Marine EM (MT/CSEM) and seismic data (land and ocean) will be inverted individually and jointly using advanced 3D TTI algorithms. Numerical geodynamic modeling will simulate tectonic processes and predict future geological scenarios.
Our findings could establish a framework for TPMF-driven research in other tectonically active regions associated with NatH2 production and geohazards. The GEMANFLOW collaborative research will generate a series of joint seismic-EM 3D tomography models that describe viscous mantle flows and lithospheric structures, offering new insights into the dimensionality of TPMF, as well as the melt, heat, and fluid flows that manifest as a geothermal network. Characterizing such dynamic processes is crucial for advancing green energy solutions and gaining new insights to predict and mitigate the impact of volcanic geohazards. Humanitarian Geophysics encompasses these topics, a research theme central to NSF’s Division of Earth Sciences.
The project's applications extend to risk mitigation, scientific advancements, and environmental impact. GEMANFLOW aims to contribute to climate change models and conservation efforts by understanding the interplay between tectonics, amphibious geothermal networks, and biogeochemical cycles.
GEMANFLOW experiment survey layout: Deployment of 15 OBS and 30 OBEM marine instruments for simultaneous acquisition of seismic, MT, and csem datasets.
