Seismic evidence for oceanic plate delamination offshore Southwest Iberia João C. Duarte, Nicolas Riel, Chiara Civiero, Sónia Silva, Filipe M. Rosas, Wouter P. Schellart, Jaime Almeida, Pedro Terrinha, António Ribeiro Nature Geoscience, 2025 Subduction of oceanic lithosphere and delamination of continental lithosphere constitute the two predominant mechanisms by which the Earth’s surface is recycled into the mantle. Continental plate delamination typically occurs in collisional orogens by the separation of the lithospheric mantle from the overlying lighter crust, aided by weak layers within continental lithosphere. By contrast, oceanic lithosphere is generally considered to be sufficiently rigid to inhibit delamination. Here we show from seismic imaging and numerical simulations that delamination of oceanic lithosphere is occurring offshore Southwest Iberia. Specifically, seismic tomography reveals a high-velocity anomaly that we interpret as a delaminating block of old oceanic lithosphere, a process that we reproduce with numerical simulations. We propose that this process was triggered by plate convergence and assisted by a thick serpentinized layer that allows the lithospheric mantle to decouple from the overlying crust. We suggest that such oceanic delamination may facilitate subduction initiation, a long-unsolved problem in the theory of plate tectonics, and may be responsible for some of the highest-magnitude earthquakes in Europe, including the M8.5–8.7 Great Lisbon Earthquake of 1755 and the M7.9 San Vincente Earthquake of 1969.
Numerical Geodynamic Modeling of Buoyancy-Driven Tethyan-type Ophiolite Emplacement A. S. Gomes, F. M. Rosas, N. Riel, W. P. Schellart, J. Almeida, J. C. Duarte Tectonics, 2025 Ophiolites are exposed remnants of oceanic lithosphere that avoid subduction and are instead subaerially exposed, being usually emplaced onto a continental domain. One proposed emplacement mechanism, the Tethyan‐type, requires the subduction of a continental margin beneath an oceanic overriding plate (OP) and subsequent exhumation of the subducted continental crust. The extruding crust separates a portion of the overlaying plate, creating the ophiolite. Here, we use 2D gravity‐driven thermomechanical numerical models with visco‐plastic rheologies to test the sensitivity of this process to changes in the OP configuration. Specifically, for the OP, we test two end‐member plate ages (10 and 60 Myr) and the presence versus absence of a weak serpentinite layer beneath the oceanic crust, as well as the different combinations of these variables. Results show that Tethyan‐type ophiolite emplacement is physically viable under all prescribed conditions, although with significant disparities in between tests. The absence of a serpentinite layer is preferably associated with delayed crustal extrusion and with emplacement of relatively smaller ophiolites. Conversely, the presence of this weak layer leads to the decoupling of the OP's crust and mantle, and to a premature, facilitated extrusion of the continental crust across the serpentinized unit. These conditions favor emplacement of larger ophiolites, separated by also larger continental windows. Plate age has a second order influence in the emplacement process. Older plates tend to delay the onset of deep continental delamination, but at the same time tend to accelerate surface crustal extrusion.
Numerical modelling of lithosphere-asthenosphere interaction and intraplate deformation in the Gulf of Guinea Jaime Almeida, Hamzeh Mohammadigheymasi, Marta Neres, Stéphanie Dumont Tectonophysics, 2025 To present day, the phenomenon of intraplate deformation and its associated earthquakes remain elusive. In this work, we argue that intraplate deformation may result from the interaction between lithospheric and upper mantle dynamic processes. To this extent, we targeted the Gulf of Guinea and adjacent Western Africa, a region with both low plate velocities and clear asthenosphere dynamics, allowing us to isolate the individual underlying dynamic constraints which govern intraplate deformation. Thus, here we present 3D numerical geodynamic models of the asthenosphere-lithosphere interaction in the Gulf of Guinea, ran with the state-of-the-art modelling code LaMEM. We employ different initial/boundary conditions such as: (a) identical vs different spreading rates for the varying segments of the Atlantic mid-ocean ridge, (b) the presence/absence of weak zones (e.g., the Romanche/Central-African shear zones), and (c) the effect exerted by an active mantle plume, with a varying ascension velocity. Seismicity patterns was used to evaluate the models and their validity. Our results suggest that intraplate deformation within the Gulf of Guinea is influenced by the spreading rate of the mid-ocean ridge, with stress being localized around the ocean-continent transition and existing shear zones. They also suggest that the existence of an underlying stress source (e.g., a mantle plume) beneath the Cameroon region is crucial to explain the epicenter distribution/deformation in the region. • The seismic event distribution in the Gulf of Guinea can be explained by the interaction between two separate stress sources. • The presence of lithospheric weak zones allows the stress from the mid-ocean ridge to be transferred inland, with the seismicity in the Southern part of Ghana partly reflecting this process. • A mantle plume underneath the Cameroon Volcanic Line can explain the seismic events in the region.
Subduction initiation triggered the Caribbean large igneous province Nicolas Riel, João C. Duarte, Jaime Almeida, Boris J. P. Kaus, Filipe Rosas, Yamirka Rojas-Agramonte, Anton Popov Nature Communications, 2023 Subduction provides the primary driving force for plate tectonics. However, the mechanisms leading to the formation of new subduction zones remain debated. An example is the Lesser Antilles Arc in the Atlantic. Previous initiation mechanisms have implied the transmission of subduction from the Pacific Ocean or the impact of a plume head. Here, we use geodynamic models to simulate the evolution of the Caribbean region during the Cretaceous, where the eastern Pacific subduction triggered the formation of a new subduction zone in the Atlantic. The simulations show how the collision of the old Caribbean plateau with the Central America margin lead to the formation of a new Atlantic subduction zone by polarity reversal. The results further show how subduction renewal on the back of the old Caribbean plateau (present-day Central America) resulted in a major mantle flow reorganization that generated a subduction-induced plume consistent with the formation of the Caribbean Large Igneous Province.
Self-replicating subduction zone initiation by polarity reversal Jaime Almeida, Nicolas Riel, Filipe M. Rosas, João C. Duarte, Boris Kaus Communications Earth and Environment, 2022 Subduction zones have recurrently formed on Earth. Previous studies have, however, suggested that they are unlikely to start in the interior of a pristine ocean. Instead, they seem to be more likely to form from another pre-existing subduction zone. One widely cited conceptual model to start new subduction zones is polarity reversal, resulting from the shutdown of a pre-existent subduction zone due to the arrival of a buoyant block at the trench. However, the dynamic conditions by which this process occurs remain elusive. Here, we present 3D numerical models of subduction zone initiation by polarity reversal resulting from the arrival of an oceanic plateau at the trench. Our results show that this process is more likely to occur for old subducting plates and narrow plateaus, and that new subduction zones can form from previous ones in a self-replicating manner, without requiring any other external tectonic forcing.
A computational diffusion model to study antibody transport within reconstructed tumor microenvironments Ana Luísa Cartaxo, Jaime Almeida, Emilio J. Gualda, Maria Marsal, Pablo Loza-Alvarez, Catarina Brito, Inês A. Isidro BMC Bioinformatics, 2020 Background Antibodies revolutionized cancer treatment over the past decades. Despite their successfully application, there are still challenges to overcome to improve efficacy, such as the heterogeneous distribution of antibodies within tumors. Tumor microenvironment features, such as the distribution of tumor and other cell types and the composition of the extracellular matrix may work together to hinder antibodies from reaching the target tumor cells. To understand these interactions, we propose a framework combining in vitro and in silico models. We took advantage of in vitro cancer models previously developed by our group, consisting of tumor cells and fibroblasts co-cultured in 3D within alginate capsules, for reconstruction of tumor microenvironment features. Results In this work, an experimental-computational framework of antibody transport within alginate capsules was established, assuming a purely diffusive transport, combined with an exponential saturation effect that mimics the saturation of binding sites on the cell surface. Our tumor microenvironment in vitro models were challenged with a fluorescent antibody and its transport recorded using light sheet fluorescence microscopy. Diffusion and saturation parameters of the computational model were adjusted to reproduce the experimental antibody distribution, with root mean square error under 5%. This computational framework is flexible and can simulate different random distributions of tumor microenvironment elements (fibroblasts, cancer cells and collagen fibers) within the capsule. The random distribution algorithm can be tuned to follow the general patterns observed in the experimental models. Conclusions We present a computational and microscopy framework to track and simulate antibody transport within the tumor microenvironment that complements the previously established in vitro models platform. This framework paves the way to the development of a valuable tool to study the influence of different components of the tumor microenvironment on antibody transport.
Combining machine learning and a knowledge base for seismic data intelligence expansion 81st Eage Conference and Exhibition 2019, 2019
Analog modelling of strike-slip fault (lateral) propagation from an elastic to a viscous medium: Insights from trial experiments Comunicacoes Geologicas, 2014
RECENT SCHOLAR PUBLICATIONS
Pelletized and monolithic CuNi/CeO2 in ethanol steam reforming: stability, coke formation and steam regeneration AD Gomes, I Dancini-Pontes, P Vitor, JCL Almeida, CP Girotto, M Souza International Journal of Hydrogen Energy 222, 154292 , 2026 2026
Technical studies for offshore energy potential, geological and environmental mapping towards support of windfarm developers' decisions P Brito, F Abrantes, C Aires, J Almeida, L Batista, R Borges, P Costa, ... EGU26 , 2026 2026
Subduction invasion of the Atlantic JC Duarte, N Riel, WP Schellart, F Rosas, J Almeida EGU26 , 2026 2026
GEMMA Project: Geodynamic Insights from GNSS and Modelling in Macaronesia RMS Fernandes, J Duarte, R Ramalho, PJ González, J Almeida, ... AGU25 , 2025 2025
Seismic evidence for oceanic plate delamination offshore Southwest Iberia JC Duarte, N Riel, C Civiero, S Silva, FM Rosas, WP Schellart, J Almeida, ... Nature Geoscience 18 (10), 1034-1040 , 2025 2025
Numerical geodynamic modeling of buoyancy‐driven Tethyan‐type ophiolite emplacement AS Gomes, FM Rosas, N Riel, WP Schellart, J Almeida, JC Duarte Tectonics 44 (8), e2024TC008625 , 2025 2025 Citations: 2
The unrecognized burden of HFpEF in pacemaker patients: results from a systematic heart failure program E Santos, F Nunes, A Lobo, C Oliveira, F Rosas, P Castro, J Braga, ... Europace 27 (Supplement_1), euaf085. 565 , 2025 2025
2D Numerical modelling of continental subduction and synthetic obduction F Rosas, A Gomes, W Schellart, R Nicolas, J Duarte, J Almeida EGU General Assembly Conference Abstracts, EGU25-10088 , 2025 2025
Modes of collisional orogenic growth: forward, backward and thermally induced N Rodrigues, N Riel, F Rosas, J Almeida, A Gomes, J Duarte EGU General Assembly Conference Abstracts, EGU25-12306 , 2025 2025
Insights into plume-ridge-transform fault interactions as derived from 3D numerical geodynamic modelling of the Azores Triple Junction J Almeida, J Duarte, F Rosas, RS Ramalho, R Fernandes EarthArXiv , 2025 2025
Numerical modelling of lithosphere-asthenosphere interaction and intraplate deformation in the Gulf of Guinea J Almeida, H Mohammadigheymasi, M Neres, S Dumont Tectonophysics 895, 230581 , 2025 2025
3D numerical geodynamic modelling of plume-ridge-transform fault interactions in the Azores triple junction J Almeida, J Duarte, F Rosas, RMS Fernandes, R Ramalho AGU Fall Meeting Abstracts 2024 (323), V11F-323 , 2024 2024
Numerical and analogue modelling of boudinage under non-coaxial shear strain F Rosas, A Gomes, J Almeida, J Duarte, N Riel, W Schellart European Geosciences Union General Assembly 2024 (EGU24), 12208 , 2024 2024
A new geodynamic model of the Azores archipelago: preliminary results J Almeida, J Duarte, F Rosas, R Fernandes, F Geraldes, L Carvalho, ... European Geosciences Union General Assembly 2024 (EGU24), 13464 , 2024 2024
Crust-mantle delamination enables continental subduction and flake tectonics: insights from numerical modelling N Rodrigues, F Rosas, N Riel, J Almeida, A Gomes, J Duarte European Geosciences Union General Assembly 2024 (EGU24), 13652 , 2024 2024
Proto-ophiolite serpentinization may influence ophiolite emplacement: Insights from numerical models A Gomes, F Rosas, N Riel, J Duarte, WP Schellart, J Almeida European Geosciences Union General Assembly 2024 (EGU24), 10540 , 2024 2024
Enhanced insight into Ghana’s seismicity through a refined crustal velocity model and earthquake focal mechanisms H Mohammadigheymasi, Z Xiao, SM Mousavi, M Jamalreyhani, J Almeida, ... EGU General Assembly 2024 , 2024 2024 Citations: 3
New insights on geodynamic modelling of the Central Group of the Azores archipelago RMS Fernandes, J Almeida, J Duarte, FM Rosas, R Ramalho, ... AGU Fall Meeting Abstracts 2023, G12A-03 , 2023 2023
Geodynamic modelling of continental subduction beneath oceanic lithosphere F Rosas, A Gomes, N Riel, W Schellart, J Duarte, J Almeida EGU General Assembly Conference Abstracts, EGU-7248 , 2023 2023
2D numerical modelling of Tethyan-type ophiolite emplacement: The role of overriding plate age, serpentinization, and OCT width. A Gomes, F Rosas, J Duarte, N Riel, W Schellart, J Almeida EGU General Assembly Conference Abstracts, EGU-7370 , 2023 2023
MOST CITED SCHOLAR PUBLICATIONS
Polarity-reversal subduction zone initiation triggered by buoyant plateau obstruction J Almeida, N Riel, FM Rosas, JC Duarte, WP Schellart Earth and Planetary Science Letters 577, 117195 , 2022 2022 Citations: 51
Subduction initiation triggered the Caribbean large igneous province N Riel, JC Duarte, J Almeida, BJP Kaus, F Rosas, Y Rojas-Agramonte, ... Nature Communications 14 (1), 786 , 2023 2023 Citations: 45
Self-replicating subduction zone initiation by polarity reversal J Almeida, N Riel, FM Rosas, JC Duarte, B Kaus Communications Earth & Environment 3 (1), 55 , 2022 2022 Citations: 38
A computational diffusion model to study antibody transport within reconstructed tumor microenvironments AL Cartaxo, J Almeida, EJ Gualda, M Marsal, P Loza-Alvarez, C Brito, ... BMC bioinformatics 21 (1), 529 , 2020 2020 Citations: 11
Analogue modelling of brittle shear zone propagation across upper crustal morpho-rheological heterogeneities AS Gomes, FM Rosas, JC Duarte, WP Schellart, J Almeida, R Tomás, ... Journal of Structural Geology 126, 175-197 , 2019 2019 Citations: 11
Impact of crustal rheology and inherited mechanical weaknesses on early continental rifting and initial evolution of double graben structural configurations: Insights from 2D … ME Oliveira, AS Gomes, FM Rosas, JC Duarte, GS Franca, JC Almeida, ... Tectonophysics 831, 229281 , 2022 2022 Citations: 7
Delamination of oceanic lithosphere in SW Iberia: a key for subduction initiation? J Duarte, N Riel, C Civiero, F Rosas, W Schellart, J Almeida, S Silva, ... Geophysical Research Abstracts 21 , 2019 2019 Citations: 5
Analog modelling of strike-slip fault (lateral) propagation from an elastic to a viscous medium: insights from trial experiments FM Rosas, P Terrinha, J Duarte, L Baptista, C Kullberg, J Almeida, ... Commun Geol 101, 1429-1432 , 2014 2014 Citations: 5
Enhanced insight into Ghana’s seismicity through a refined crustal velocity model and earthquake focal mechanisms H Mohammadigheymasi, Z Xiao, SM Mousavi, M Jamalreyhani, J Almeida, ... EGU General Assembly 2024 , 2024 2024 Citations: 3
Numerical geodynamic modeling of buoyancy‐driven Tethyan‐type ophiolite emplacement AS Gomes, FM Rosas, N Riel, WP Schellart, J Almeida, JC Duarte Tectonics 44 (8), e2024TC008625 , 2025 2025 Citations: 2
Numerical modelling of induced subduction initiation: thermal control exerted by plate ages in polarity reversal during plateau docking. J Almeida, N Riel, F Rosas, J Duarte Geophysical Research Abstracts 21 , 2019 2019 Citations: 1
Pelletized and monolithic CuNi/CeO2 in ethanol steam reforming: stability, coke formation and steam regeneration AD Gomes, I Dancini-Pontes, P Vitor, JCL Almeida, CP Girotto, M Souza International Journal of Hydrogen Energy 222, 154292 , 2026 2026
Technical studies for offshore energy potential, geological and environmental mapping towards support of windfarm developers' decisions P Brito, F Abrantes, C Aires, J Almeida, L Batista, R Borges, P Costa, ... EGU26 , 2026 2026
Subduction invasion of the Atlantic JC Duarte, N Riel, WP Schellart, F Rosas, J Almeida EGU26 , 2026 2026
GEMMA Project: Geodynamic Insights from GNSS and Modelling in Macaronesia RMS Fernandes, J Duarte, R Ramalho, PJ González, J Almeida, ... AGU25 , 2025 2025
Seismic evidence for oceanic plate delamination offshore Southwest Iberia JC Duarte, N Riel, C Civiero, S Silva, FM Rosas, WP Schellart, J Almeida, ... Nature Geoscience 18 (10), 1034-1040 , 2025 2025
The unrecognized burden of HFpEF in pacemaker patients: results from a systematic heart failure program E Santos, F Nunes, A Lobo, C Oliveira, F Rosas, P Castro, J Braga, ... Europace 27 (Supplement_1), euaf085. 565 , 2025 2025
2D Numerical modelling of continental subduction and synthetic obduction F Rosas, A Gomes, W Schellart, R Nicolas, J Duarte, J Almeida EGU General Assembly Conference Abstracts, EGU25-10088 , 2025 2025
Modes of collisional orogenic growth: forward, backward and thermally induced N Rodrigues, N Riel, F Rosas, J Almeida, A Gomes, J Duarte EGU General Assembly Conference Abstracts, EGU25-12306 , 2025 2025
Insights into plume-ridge-transform fault interactions as derived from 3D numerical geodynamic modelling of the Azores Triple Junction J Almeida, J Duarte, F Rosas, RS Ramalho, R Fernandes EarthArXiv , 2025 2025
