Workshop on High-Pressure Mineral Physics and Geophysics Applications

February 2 – 6, 2026

ICTP-SAIFR, São Paulo, Brazil

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Materials simulations bring powerful methods for predicting the physical properties of complex mineral phases, assemblages, and melts under the extreme conditions expected in Earth’s interior (~6,500 K and 3.6 Mbar). They play a central role in probing the deep Earth and have brought us to the threshold of developing a general predictive theory of planetary interiors grounded in their material properties.
This workshop advances this vision by bringing together a multidisciplinary team of scientists to discuss the integration between three core fields of computational geophysics: mineral physics, seismology, and geodynamics.

 

 

Organizers:

  • Renata MM Wentzcovitch (Columbia University, New York, USA)
  • Carlos Alberto Moreno Chaves (IAG, USP, São Paulo, BR)
  • Caetano Miranda (IF-USP, São Paulo, BR)
  • John Hernlund (Earth-Life Science Institute, Tokyo-Tech, Tokyo, JP)
  • Alexandre Reily Rocha (IFT/UNESP, ICTP/SAIFR, São Paulo, BR)
  • Victor Sacek (IAG, USP, São Paulo, BR)

 

Announcement:

Click HERE for online application
Application deadline: December 20, 2025

Invited Speakers

Invited speakers

*Virtual speakers

Registration

Announcement:

Click HERE for online application
Application deadline: December 20, 2025

Program

 The schedule might be changed.

Posters

  • Aguilar, Sebastian Camilo (Universidade Estadual De Campinas, Brazil): New Paleomagnetic Data from South America: Effects of The South Atlantic Magnetic Anomaly on Paleointensity Record

The Earth’s magnetic field (EMF), generated by geodynamo processes, varies across multiple timescales ranging from years to billions of years. Integrated analyses of paleodirectional and paleointensity data over the past 10 million years reveal persistent non-dipolar features in the Southern Hemisphere, linked to the South Atlantic Magnetic Anomaly. However, the spatial and temporal coverage of high-quality paleomagnetic data remains uneven, particularly low in this region. Paleointensity data from 41 sites from Colombia, Brazil, and Argentina were collected using multiple experimental methods, including Triaxe, Wilson, Thermal Thellier, Microwave Thellier, and the Double Heating Technique of Shaw (DHT-Shaw). Thermomagnetic curves exhibit a susceptibility drop between 550 °C and 580 °C, indicative of low-Titanium titanomagnetite. IRM curves with saturation fields below 300 mT confirm the presence of low coercivity minerals. FORC analyses and Day diagrams reveal the dominance of the Pseudo Single Domain (PSD) state of the magnetic grains. Out of 332 specimens analysed in paleointensity experiments, approximately 20% met the selection criteria. Virtual Dipole Moments (VDMs) ranged from 2.45× 10²² Am² and 8.02× 10²² Am² (8 sites in Argentina), 1.64× 10²² Am² to 9.29× 10²² Am² (5 sites in Colombia); and 5.17× 10²² Am² to 5.49× 10²² Am² (2 sites, in Brazil). Normal and reversal sites exhibit paleointensity values within the 95% confidence limits of geomagnetic field models such as PADM2M and MCADAM 1b, whereas transitional data display significantly lower values. The new Paleomagnetic data from various volcanic bodies in South America will contribute to expanding the database for the last 10 My, especially in a sparsely populated region, thereby enhancing the model’s accuracy and providing better constraints on their boundary conditions.

  • Antonelli, Alex (Gleb Wataghin Institute of Physics/State University of Campinas, Brazil): Non-equilibrium free-energy calculation of phase-boundaries using LAMMPS

In this seminar, a methodology for computing the phase boundaries of systems described by interatomic potentials will be presented. This methodology uses the dynamic Clausius–Clapeyron integration (dCCI) method within the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) code [1]. The dCCI method provides coexistence curves spanning a wide range of thermodynamic states using a single, relatively short, non-equilibrium simulation. State-of-the-art non-equilibrium free energy methods that enable us to compute Gibbs free energy over a wide range of pressures and/or temperatures will be reviewed. The dCCI method will be presented in detail. As an application, it will be discussed the results for the phase diagram of silicon at pressures ranging from 0 to 15 GPa and temperatures ranging from 400 K to the liquid phase, in order to obtain the phase boundaries and triple point between the diamond, liquid, and β-Sn phases. [1] Samuel Cajahuaringa and Alex Antonelli, Comput. Mater. Sci. 207, 111275 (2022).

  • Barros Sousa, Joaquim De Paula (Universidade de São Paulo, Brazil): Investigating the Mechanical Properties of Materials in Planetary Interiors via Computational Simulations

Investigating the mechanical properties of materials under extreme conditions is essential for comprehending the stability and behaviour of phases that may exist in planetary interiors. The central aim of this research is to determine the elastic mechanical properties of the orthorhombic P21212 phase of methane (CH4), theoretically predicted, using first-principles simulations. Secondary objectives involved calculating the elastic moduli via two distinct methods: energy vs. strain and stress vs. strain. To validate the methodology, we studied the cubic I Fm3m phase, which is stable at low temperatures and pressures and for which experimental data exist. Moreover, this work also sought to understand the effect of dispersion corrections, which are significant in molecular crystals, on the structural and mechanical properties of these systems.

  • Benevides, Artur (Observatorio Nacional, Brazil): Deep Lithospheric Geophysical Constraints on the Parnaíba Basin: Insights from Integrated Magnetotelluric and Seismological Models

 

  • Caiza Grijalva, Ricardo (Geoazur – Universite Cote D’Azudr, France): Elastic Full Waveform Inversion of Multicomponent Data appliying Spectral Element Methods.

Full Waveform Inversion (FWI) nowadays is positioned as a sophisticated technique that enables the reconstruction of several physical properties of earth subsurface as wave propagation velocities (Vp, Vs), density (ρ), anisotropic pa- rameters, attenuation and others. Updating these properties imposes some difficulties because parameters of different nature may imprint a coupled effect visible in the seismic response known as trade-off or cross-talk between parameters [Operto et al., 2013, Carcione et al., 1992]. Considering the Elastic Properties of the Earth steps up the inversion proce- dure enabling the possibility of working with Multicomponent data with instruments as Ocean Bottom Nodes (OBNs) which register pressure, radial, transverse and vertical components, etc. This review aims to better understand the Multicomponent Multiparameter Elastic FWI, their challenges, state of the art and future promising applications into research, industry and environmental fields, focused on off-shore targets with potential extension to on-shore observations.

  • Carrez, Philippe (University of Lille, France): Multiscale modeling of plastic properties under extreme conditions

The transport of heat from the interior of the Earth drives convection in the mantle, which involves the deformation of solid rocks over billions of years. Significant advancements have been made over recent years to study lower mantle assemblages under relevant pressure and temperature conditions. Nevertheless, the natural strain rates are 8 to 10 orders of magnitude lower than those observed in the laboratory. To overcome this limitation on strain rates, multi-scale numerical modelling appears nowadays as a reliable candidate for the determination of rheological properties, once the physical mechanisms of the deformation of rocks and their constituent minerals have been identified. This presentation will demonstrate how this theoretical approach can be used to describe the elementary deformation mechanisms of bridgmanite and periclase. We will show how results from numerical modelling compare with available experimental results in order to validate the theoretical approach. In a subsequent phase, the impact of very slow strain rates on the activation of the aforementioned mechanisms will be discussed to highlight the fact that significant alterations in deformation mechanisms can occur in response to changes in strain rate.

  • Ciardelli, Caio (Institute of Astronomy, Geophysics, and Atmospheric Sciences – University of São Paulo, Brazil): Cross-compatibility of 3D Models of the South American Mantle

We compare eight regional and global seismic tomography models beneath South America using a tetrahedral mesh and evaluate their similarity using volume-weighted cosine similarity (CS) and root mean square (RMS). Building on an extensive review of previous regional and global studies, we examine differences in model parameterization, velocity-to-density conversion strategies, and the influence of crustal uncertainties, all of which affect gravity predictions. In the upper mantle, CS values among most regional models range from 0.4 to 0.8, with the strongest agreement observed between SA2019 and SAAM23. In the lower mantle, CS values fall below 0.4 for most model comparisons, except among global models, which maintain moderate internal similarity (CS ≈0.5). Normalized RMS values are generally higher for regional models, reflecting larger differences in anomaly amplitude and distribution relative to global models. Velocity perturbations are converted to density perturbations using three methods: a constant scaling factor, a smoothed depth-dependent profile from joint inversion, and a profile from thermodynamic modeling with BurnMan. These methods influence the amplitude of predicted gravity disturbances, which range from 14 to 138 mGal, but have limited effect on spatial patterns. Predicted upper-mantle gravity disturbances from all models are anti-correlated with the observed upper-mantle field (CS ≈-0.5), likely reflecting compositional effects such as iron depletion in cratonic lithosphere that are not captured by the velocity-to-density scaling. However, among the models, SAM5_P_2019 yields the highest CS with satellite gravity when considering the gravitational effect of the whole mantle, with CS near 0.5. Models with strong lithospheric velocity perturbations tend to produce gravity disturbances with amplitudes greater than observed, indicating differences in the depth distribution of density. The three scaling methods tested yield similar gravity patterns, with differences mostly in amplitude. BurnMan-based scaling gave slightly better results than the other two methods, but the improvement was moderate. Allowing for lateral variations in scaling—guided by seismic or geodynamic models—would likely improve agreement with observed gravity. Further progress will require denser seismic coverage—especially finite-frequency teleseismic data—joint inversions including gravity and geoid constraints, and better estimates of mantle composition from geochemistry, geodynamics, and mineral physics.

  • Contiero, Klaus (IAG/USP, Brazil): Seismic Attenuation in South America from Multiple ScS Wave Phases

Seismic attenuation is one of the most important factors for characterizing the mantle structure, and it also provides information about thermal structure, fluid presence and composition of the mantle, especially in the case of shear waves. The multiple ScS phases (S waves reflected at the mantle-core interface), with nearly vertical geometry and one of the cleanest phases traveling through the mantle, has been widely used to determine attenuation. At epicentral distances of up to 20°, the ScS and ScS2 phases are recorded with high amplitudes at relatively low frequencies (f < 50 mHz) and without interference with signals from other main phases. It is assumed that the long-period ScS and ScS2 waveforms are insusceptible to multipath and amplification by layers and heterogeneity in the lithosphere and deep mantle. In this research project, we will use new seismological stations, with the improvement in the number of stations in recent decades to increase coverage on the South American platform, mainly in Brazil (notably the XC network, in the Paraná (PB), Chaco-Paraná (CB) and Pantanal (PtB) Basins), to calculate the ScS2/ScS amplitude ratios and an updated map of the quality factor Q for South America. Our database will consist of data from the XC network, notably from stations west of the Paraná Basin, to obtain data on epicentral distances of up to 20° and low frequency, as used in recent studies of this type, and synthetic waveforms. Therefore, seeking to expand the understanding of the dynamics of the mantle beneath South America, especially in Brazil, our objective in this doctoral project is to understand how seismic attenuation can bring links with the geodynamics of the region, such as mantle convection and plate tectonics, especially regarding the presence of fluids, combining data from velocity anomalies and seismic attenuation to better understand the mechanisms responsible for the movement of the South American plate, the evolution of the lithosphere in this region and obtain information on how the subduction of the Andes can influence geodynamic processes.

  • Costa, Joao Antenogenes Prudencio Da (Instituto de Ciência e Tecnologia UNESP – Câmpus de Sorocaba, Brazil): Estudo dos impactos pedagógicos no ensino de temas sobre de meio ambiente, geologia e astronomia em escolas de ensino fundamental e médio.

O senso de conexão, identificação e interesse dos estudantes e professores por temas que envolvem meio ambiente, geologia e astronomia estão relacionados ao sentimento de pertencimento a um lugar, sendo que este mesmo é parte integrante do meio ambiente geral, incluindo a comunidade a que ele pertence. Uma das tônicas da agenda 21 e projeção para 2030 é a construção de uma educação para o meio ambiente sustentável e abrindo assim uma profícua oportunidade de desenvolvimento da sensibilidade ambiental nas escolas.Segundo os Parâmetros Curriculares para o Ensino Fundamental (6º ao 9° anos) e Parâmetros Curriculares Nacionais (Ensino Médio) Parte III – Ciências da Natureza, Matemática e suas Tecnologias, as ciências ambientais têm por base os conhecimentos das disciplinas de Física, Química, Matemática, Biologia, Geografia e Direito Ambiental. O aprofundamento nestas disciplinas favorece a compreensão dos processos ambientais de forma geral, podendo-se avançar em questões ambientais mais relevantes, tais como, os temas sobre Geologia, Geomorfologia, Recursos Hídricos, Climatologia, Ecossistemas Aquáticos Continentais e Marinhos, Engenharia e Computação. A transdisciplinaridade e a interdisciplinaridade devem, segundo a Lei de Diretrizes e Bases da Educação Nacional (LDB) ou Lei nº 9.394/1996 nos artigos 3º, 6º 10º, 12º e 24º afim de proporcionar um desenvolvimento do aprendizado dos temas das ciências ambientais, citados nas disciplinas que compõem a educação básica, desde o ensino fundamental até o médio (BRASIL, 2024). Contudo, seu teor não contempla os modos de abordagem que viabilizam a execução da práxis docente. A pesquisa em andamento na pós-graduação em ciências ambientais do ICTS-Unesp, se endereça a esta operação, no âmbito de saber quais os temas e práticas de ensino ambiental de maior ou menor aceitação e afim de identificar e qualificar variáveis de sensibilização presentes nas aulas das disciplinas utilizando questionários de múltipla alternativa compostos por escalas de satisfação Likert/Guttman, aplicadas em escolas públicas.

  • De Sá Fernandes, Yasmin (Instituto de Geociências da Universidade de São Paulo, Brazil): Crystallization experiments of high-potassium, silica-undersaturated rocks at 1 GPa

The study of the crystallization conditions of a high-potassium, silica-poor picrite from Santa Bárbara Island, located in the Abrolhos Archipelago, integrates the Petrobras Project 2024/00039-9, titled “Magmatismo alcalino do SE e a pluma de Vitória-Trindade: plumbing systems e temperaturas do manto” (SE Alkaline Magmatism and the Vitória–Trindade Plume: plumbing systems and mantle temperatures). This project seeks to better understand the petrogenetic processes associated with intraplate alkaline magmatism in southeastern Brazil and to constrain the thermal and chemical characteristics of the mantle source involved in the generation of these magmas. To investigate the crystallization sequence and phase stability of the Santa Bárbara picrite, controlled high-pressure and high-temperature experiments were conducted at the Laboratory of Experimental Petrology and Geochemistry of the Institute of Geosciences at the University of São Paulo. The experimental procedure involved preparing assemblies in which a synthetic starting material was formulated to replicate the natural bulk composition of the picrite. This powder was loaded into graphite capsules, which were subsequently enclosed within platinum capsules. The use of graphite served to buffer oxygen fugacity and, critically, to prevent iron loss to the platinum container, thus ensuring that the Fe/Mg ratios remained representative of natural conditions. The assembled capsules were placed into a 200-ton end-loaded Bristol-type piston-cylinder apparatus, where four separate runs were performed at a constant pressure of 1 GPa and temperatures of 1300 °C, 1250 °C, 1200 °C, and 1150 °C. After quenching, the recovered charges were mounted and analyzed using Scanning Electron Microscopy (SEM), allowing detailed identification of the crystallized mineral phases and textural relationships. These observations provide insights into the liquidus and sub-liquidus mineral assemblages, contributing to the reconstruction of the magmatic evolution of this highly primitive melt.

  • Do Carmo, Danusa (CNPEM – Brazilian Center for Research in Energy and Materials, Brazil): Sussuarana beamline

High energy X-ray beamlines are useful tools for studying thick solid materials. The penetration power of these beams coupled with their high flux allows rapid collection of powder diffraction data and monitoring in-situ processes in samples up to several millimeters in thickness. For phase-II of Sirius high energy beamlines are being designed, such as Sussuarana beamline. This will be the highest energy beamline in Sirius so far, in the range of 30 to 200 keV, and it is planned to work with both white and monochromatic beams. X-ray diffraction and imaging techniques will be available as well as experimental setups for thermomechanical testing of samples of interest in metallurgy under real operating conditions and large volume press for in situ processing/synthetizing materials under high pressure and temperature.

  • Dos Santos, Rodrigo Neves (UFBA, Brazil): DFT testing of q-Eos in the NaCl, MgO and FeSi

The equation of state for solids in high pressure is an open problem. Much of the discussion revolves around the infinite bulk modulus derivative. The most commonly used equation, the Birch-Murnaghan equation, does not have this problem. The B’_\infty tends to 3 as many experimental dates indicate. However, it has an intrinsic problem, it total energy decreases in very high pressure if the equilibrium derivative of bulk modulus, B’_0, is less 4 instead of increasing, as the physical intuition suggest. To adress this issues a new equation of state is proposed, it is based on Tsallis mathematical development in nonextensive statistical mechanics: the strain is generalized using the q-logarithm and some assumption liking q with equilibrium derivative allows writing the complete series of Birch-Murnaghan free energy in a simple way, resulting in pressure p(v)=-B_0v^-q ln_{q*}(v). Beyond solving the equilibrium derivative of bulk modulus problem, the new equation satisfies some criteria advocated by F.D Stacey for application in seismological dates: When v goes to 0 p*B’(p)/B(p)=1, that it, in very high pressure the derivative of bulk modulus must approximates of B’_{\infty}; and B’(p)>5/3, because this is the limit impose by the electron gas in quantum mechanics view point. In this work the eficiency of q-Eos is compared with the Birch-Murnaghan equation of third order and Murganhan equation using the Density Functional Theory (DFT) implemment in the Quantum Espresso (QE). The materials chosen for this porpuse are NaCl, MgO and FeSi because the first two are well-known material in Physics and the latter is very important in seismological study.

  • Dutra, Alanna (Universidade Federal da Bahia, Brazil): The electrical structure of the lithosphere in the southeastern margin of the Amazonian craton

A broad zone of high electrical conductivity, the Paraguay–Araguaia Conductivity Anomaly (PACA), extends for over 1,000 km along the southeastern margin of the Amazonian Craton. To constrain its geometry and origin, we acquired a 200 km magnetotelluric (MT) profile across the northern PACA, intersecting the Goiás Magmatic Arc and Araguaia Belt in Central Brazil. Three-dimensional resistivity models reveal that the PACA comprises at least two contiguous conductive bodies in the upper to middle crust. The elevated conductivity likely results from sulfide mineralization formed in an inter-arc or back-arc basin and later tectonically emplaced beneath the western Goiás Arc. The anomaly is truncated westward by a subvertical resistor associated with the Transbrasiliano Lineament (TBL), interpreted as a Neoproterozoic–Cambrian mylonitic shear zone developed during the collision between the Amazonian Craton and proto-West Gondwana. Our results favor an oblique continental collision rather than east-dipping oceanic subduction, suggesting that the PACA marks the paleo-boundary of the Amazonian plate.

  • Faria Nishimi, Sora Satie (Instituto de Astronomia, Geofísica e Ciências Atmosféricas – USP, Brazil): Numerical modeling of the formation and migration of mid-ocean ridges

The planet Earth is unique in the Solar System because it operates under a fully developed regime of plate tectonics, in which the lithosphere is fragmented into rigid plates that move, deform, and interact over geological time. A key element of this regime is the continuous generation of new oceanic lithosphere at mid-ocean ridges, where mantle material ascends, melts, and solidifies to form new crust. Understanding this process requires investigating how crustal and mantle rocks respond to thermal, magmatic, and tectonic conditions, as well as how these conditions evolve through time. The main objective of this project is to evaluate how thermal, rheological, and kinematic parameters influence the formation and evolution of oceanic lithosphere. Particular attention is given to the circumstances under which these factors may either stabilize the axis of a mid-ocean ridge or cause its abrupt lateral relocation into nearby regions, a phenomenon known as a ridge jump. Such events can significantly modify the architecture of ocean basins and the distribution of crustal ages. To address these questions, the project employs Mandyoc, a numerical code capable of simulating the thermomechanical evolution of the lithosphere and upper mantle in a variety of geodynamic settings. This tool enables the exploration of magmatic processes and the conditions that lead to axis stability or migration. The numerical results will be compared with natural examples where ridge jumps have been proposed, providing a framework for interpreting patterns observed in real seafloor spreading systems. We’ve already obtained several results indicating that the interaction between mantle plumes and the overlying lithosphere plays a key role in modifying the thermal structure and weakening the plate. Our preliminary simulations show that plume-related heating can thin the lithosphere asymmetrically, shifting magmatic activity away from the original ridge axis and promoting the onset of off-axis melting zones. These zones may evolve into new spreading centers, setting the stage for a ridge jump.

  • Fialho, Thereza Mayra De Souza (IAG-USP, Brazil): Seismic anisotropy analysis of the upper mantle beneath the Borborema Province from XKS splitting measurements

Seismic anisotropy refers to the directional variation in the propagation speed of seismic waves and the polarization of particle motions, resulting from the elastic properties of rocks, which reflect the crystalline alignment and past stress states to which they have been subjected. This condition is observed in various regions of the Earth’s mantle, such as the D” layer and the upper mantle, where the preferential alignment of olivine is often associated with lithospheric motion and ancient orogenic processes. The study of seismic anisotropy, therefore, provides valuable insights into the Earth’s internal dynamics and the structure of its layers, allowing inferences about the direction of asthenospheric flow and the orientation of mantle minerals. The Borborema Province (BORB), located in northeastern Brazil, is a region of particular interest due to its unique geological features, including large shear zones, significant seismic activity, multiple magmatic events, and geophysical evidence of crustal and lithospheric thinning. Despite the tectonic complexity of the region, which dates back to the Precambrian and was affected by orogenic cycles such as the Brasiliano, the relationship between these factors and lithospheric evolution remains a topic of debate, particularly regarding the presence of seismic anisotropy and the influence of the underlying mantle. Previous studies suggest that Borborema may have undergone lithospheric delamination and basal erosion processes, resulting in a thinner and more unstable lithosphere. The splitting parameters of XKS shear waves (such as SKS, SKKS, PKS, and PKKS) derived from shear-wave splitting (SWS) analyses from previous research suggest the absence of regional-scale anisotropic structures associated with the province’s interior. This could support models postulating minimal deformation of the lithospheric mantle. In this context, the delamination of an anisotropic lithosphere during Cenozoic volcanism, which could have erased ancient fossil lithospheric structures, is considered unlikely, as the necessary volcanism is not geologically recorded. These interpretations can be complemented by integrating higher-resolution data and exploring alternative hypotheses, such as the presence of heterogeneous or overlapping anisotropy at different depths. Therefore, in this master’s project, we aim to expand the analysis of seismic anisotropy in the Borborema Province using the XKS wave splitting technique, increasing azimuthal coverage and expanding the seismic network. A more detailed study of anisotropic parameters will allow us to confirm or refute previous hypotheses, offering new perspectives on the region’s lithospheric evolution and its interaction with the underlying mantle, contributing to the understanding of the tectonic processes that shaped the area over time. Moreover, the expected results have the potential to establish new foundations for geodynamic models applicable to other tectonically complex regions, providing fresh insights into lithosphere-mantle interaction in scenarios of crustal thinning and tectonic reactivations.

  • França, George Sand Leão Araújo De (Universidade de São Paulo, Brazil): Anisotropy of the Upper Mantle in Brazil and Asthenospheric Flow around the Amazonian craton

This paper investigates the intricate dynamics of upper mantle anisotropy in Brazil, with a specific focus on understanding the asthenospheric flow patterns surrounding the Amazon craton. employing advanced seismic analysis techniques and using data from the region, the study aims to unravel the complex interplay between geological structures and seismic wave properties. A significant contribution of this research is the establishment of a dedicated Brazilian database named SplitWave, aimed at facilitating data access for researchers and fostering collaboration in the field of upper mantle anisotropy studies. Through a meticulous examination of shear wave splitting and SKS wave analysis, this research provides a comprehensive understanding of the geological evolution and tectonic processes shaping the Brazilian lithosphere. The findings reveal a substantial correlation between upper mantle anisotropy and asthenospheric flow patterns, offering valuable insights into the ongoing geodynamics processes and tectonic interactions influencing the Brazilian lithosphere. By shedding light on the intricate relationship between mantle dynamics and continental tectonics, this study not only enhances our comprehension of Brazil’s geological history but also contributes significantly to the broader field of geosciences. The insights gained from this research have the potential to inform future studies in seismology, tectonics, and geodynamics, thereby advancing our understanding of Earth’s deep structure and geophysical processes.

  • Gordilho Barbosa, Rafael (Faculdade de Ciências e Tecnologia – Universidade Federal de Goiás, Brazil): QuiG elastic modeling reveals HT/LP metamorphic overprint in a garnet-clinopyroxene amphibolite: an example from Western Gondwana

We report unprecedented Quartz-in-Garnet (QuiG) elastic modeling data for a garnet-clinopyroxene amphibolite sample overprinted by high-temperature metamorphism that corresponds to a Neoarchean (ca.2.65 Ga) oceanic crust metamorphosed during the Neoproterozoic (ca. 600 Ma) in the Borborema Province, NE Brazil. The data obtained from twenty quartz inclusions entrapped in the garnet indicate residual pressure (Pinc) values between -0.47(5) and -0.33 (5) GPa, suggesting a strongly tensile stress field. One population was identified based on Pinc values with an average value of -0.39(2) GPa, suggesting an elastic reset of the host-inclusion system during high temperature and low-pressure metamorphism after high-pressure conditions. Calculated isomeke using Equation of State (EoS) for almandine garnet indicates a pressure of 0.60(1) GPa at 725 ◦C with a Pinc value of -0.39(2) GPa, consistent with the stability of orthopyroxene from previous thermodynamic modeling. These findings suggest metamorphic conditions consistent with granulite facies, as evidenced by the breakdown of high-pressure mineral assemblages and the formation of orthopyroxene, alongside the regional occurrences of kyanite-bearing granulites, mylonitic migmatites, and sillimanite-bearing metapelites. Moreover, the volumetric response of quartz inclusions to pressure and temperature changes during exhumation to Earth’s surface suggests the development of tensile stresses, likely driven by a thermal influx during the exhumation of this segment of Western Gondwana. Therefore, the integration of chemical and physical methods for intensely retrograded metamorphic rocks allows an understanding of complex geodynamic processes, providing new insights into the exhumation of deeply burial rocks during the Neoproterozoic in NE Brazil.

  • Kanazawa, David Shiguekazu (Universidade Federal do Rio Grande do Sul, Brazil): Calibration accuracy of the Toroidal type apparatus

The high-pressure and high-temperature toroidal apparatus is a critical instrument developed to achieve pressures up to 12 GPa for materials synthesis and geological research. This system utilizes a pair of tungsten carbide anvils featuring a specialized toroidal profile. To enhance the working load capacity and prevent catastrophic failure under extreme stress, the anvils are laterally supported by a series of high-tensile concentric steel rings. A key component of this setup is the gasket, which serves as both the pressure medium and the seal. In our laboratory, we utilize a custom-fabricated composite ceramic gasket made by a mixture of calcium carbonate, chosen to provide necessary plasticity and flow properties, PVA, as a binder, and alumina, incorporated for its refractory characteristics and thermal stability. Accurate pressure calibration is established by observing discontinuous changes in electrical resistivity during phase transitions of standard reference metals: Bismuth Bi I-II at 2.5 GPa and Bi III-V at 7.7 GPa and Ytterbium Face centered cubic to Body centered cubic structure at 4.0 GPa. The calibration cell assembly includes an external graphite furnace, thermally treated pyrophyllite, and hexagonal boron nitride. The electrical setup employs a standard voltage measurement configuration using copper wires, a cellulose positioning sheet, and a 12V voltmeter, with the press piston electrically isolated to force current through the calibrant sample. Given that gaskets are manually manufactured in distinct batches, geometric and compositional inconsistencies can introduce sample pressure experimental error. This work presents a statistical analysis of a historical dataset comprising 185 calibration points to evaluate precision. When analyzing multiple gasket batches across different anvil pairs, the overall pressure calibration shows a variance of approximately 12%. However, this variance is pressure-dependent, 15% at 2.5 GPa, 14% at 4 GPa, and decreasing to 7% at 7.7 GPa. Notably, reproducibility improves significantly when restricting the analysis to a single pair of anvils, reducing the variance to 10% at 2.5 GPa, 9% at 4 GPa, and 5% at 7.7 GPa. These results highlight the critical influence of anvil geometry and gasket fabrication consistency on experimental reproducibility and indicate that our laboratory can reliably produce high pressure experiments.

  • Kaus, Boris Jozef Paul (Johannes Gutenberg University Mainz, Germany): Recent Advances in Computational Geodynamics

Understanding the dynamics of geoscientific processes requires numerical models that account for the underlying physics of the involved processes. Over the past few decades, large, parallel, community codes have driven significant advancements in computational geosciences. However, these monolithic codes, often written in low-level languages, optimized for CPU architectures, and comprising hundreds of thousands of lines of code, are difficult to modify and maintain. This hinders innovation, as much ongoing and future research requires incorporating additional physics or linking simulations with observations (for example, through adjoint-based inversion approaches). Magmatic and volcanic processes provide a key example of a complex system; they operate across a wide range of length and timescales, and experience phase transitions and changes in chemistry. Despite increasing capabilities for monitoring volcanoes (such as tracking ground deformation and earthquakes), linking observations to the physics of magmatic systems remains challenging, as no integrated computational model of magmatic systems currently exists. While certain parts of the problem are well understood through dedicated models and experiments, a comprehensive magmatic system model is needed to assess the relative impact of individual processes on the larger system. Importantly, the computational framework must be flexible enough to easily integrate new processes or machine learning approaches. Here, I will give an overview of our recent work in developing modular software packages in the Julia language as a replacement for monolithic community codes. These modular packages offer significant advantages: they are easier to maintain and extend, work seamlessly on GPUs, and accommodate nonlinear constitutive relationships regardless of the underlying solver discretization (finite element vs. finite difference). We are using this to develop magmatic system models that run on parallel GPU clusters and account for the visco-elasto-plastic deformation of rocks. To simulate the drastic changes in magma chemistry and viscosity during crystallization, we have developed an efficient computational thermodynamics code (MAGEMin) that integrates seamlessly with the thermo-mechanical models. Additionally, to assess the impact of model uncertainties on (surface) observations, we employ adjoint-based sensitivity kernels, computed using automatic differentiation tools. This enables a routine assessment of the impact of model uncertainties, even when the underlying model physics changes significantly.

  • Khangal, Ajinkya P. (Bhabha Atomic Research Centre, Mumbai, India, India): Synthesis of Erbium Hydride (ErH3) and its investigation under High Pressure

Rare-earth hydrides have recently emerged as fascinating candidates for high-pressure superconductivity, driven by their hydrogen-rich character and the concept of chemical pre-compression. Motivated by previous computational predictions of superconductivity in the Er–H system, I have focused my doctoral research on the synthesis and structural investigation of erbium hydrides under extreme conditions. In our experiments, higher erbium hydride phases were synthesized using high-purity erbium metal and paraffin oil as a hydrogen source, employing a laser-heated diamond anvil cell (LHDAC) at pressures around 36 GPa. The resulting phase was indexed to a cubic (FCC) structure corresponding to ErH3. We further examined its pressure-dependent behavior using in situ angle-dispersive X-ray diffraction (ADXRD) measurements with synchrotron radiation from the Indus-2 facility. Upon compression up to ~40 GPa and subsequent decompression to ambient pressure, the FCC ErH₃ phase was observed to transform into a hexagonal modification near 5.8 GPa. The corresponding equation of state (EOS) parameters were determined, providing valuable insights into the compressibility and structural stability of this hydrogen-rich phase. In addition, complementary high-pressure studies were performed on pure Er metal loaded with paraffin up to ~46 GPa. Successive structural phase transitions from hexagonal close-packed (hcp) to Sm-type and then to double hexagonal close-packed (dhcp) structures were recorded near 10 GPa and 24 GPa, respectively, consistent with previous literature. Through this work, I have gained extensive hands-on experience in diamond anvil cell techniques, laser heating, synchrotron-based XRD, and high-pressure data analysis—skills directly relevant to the theme of this workshop on high-pressure mineral physics and geophysical applications.

  • Lin, Jung-Fu (The University of Texas at Austin, United States): Elasticity and Thermal Transport of the Earth’s Interior

In this presentation, I will highlight recent mineral physics advances that enable reliable measurements of elasticity and thermal conductivity in mantle silicates and iron alloys under extreme pressure–temperature conditions. Our group has developed laser pump-probe methods capable of probing these key physical properties in heated diamond anvil cells at conditions relevant to the deep Earth. The resulting datasets provide critical constraints on seismic structures and dynamic processes operating in the lower mantle and core. By integrating mineral physics, seismological observations, and geodynamic models, we can better resolve lower-mantle mineralogy, compositional variations, and convective flow patterns. In addition, new constraints on thermal transport properties shed light on the energy budget of the deep Earth, including the heat flow that sustains mantle convection and powers the geodynamo.

  • Longuinhos Monteiro Lobato, Raphael (Universidade Federal de Lavras, Brazil): Exploring the Effects of Deformation, Dimensionality, and Composition on the Vibrational and Electronic Properties of Layered Materials

The physical and chemical properties of layered materials can be adjusted by engineering their deformation, dimensionality, and composition, which have vibrational fingerprints. Here, we present our findings on the influence of deformation on lattice vibrations in monolayer gallium selenide [1], dimensionality on Raman and infrared spectra and mechanical properties in gallium sulfide [2] and talc [3] and on the electronic band gap in phlogopite [4], chemical composition on the vibrational and mechanical properties of jacutingaite and tilkerodeite [5] and clinochlore [6], and electronic structure in phlogopite [3]. Acknowledgements: Fapemig, Capes, CNPq, INCT, FINEP, CENAPAD-SP, SDumont Supercomputer References: [1] R. Longuinhos and J. Ribeiro-Soares, Phys. Rev. Appl. 11, 024012 (2019). [2] R. Longuinhos et al., Phys. Chem. Chem. Phys. 26, 27260 (2024). [3] R. Longuinhos et al., J. Phys. Chem. C. 127, 5876 (2023). [4] A. R. Cadore et al., 2D Mater 9, 035007 (2022). [5] R. Longuinhos and J. Ribeiro-Soares. J. Appl. Phys. 130, 015105 (2021). [6] N. M. Kawahala et al., npj 2D Mater. Appendix 9:16 (2025).

  • Martinez, Guilherme Annes (Universidade Federal do Rio Grande do Sul – UFRGS, Brazil): PARTITIONING AND DISTRIBUTION OF MOLECULAR HYDROGEN IN MANTLE MINERALS AND MELTS UNDER SUPERSATURATED CONDITIONS: AN EXPERIMENTAL STUDY UNDER LOW OXYGEN FUGACITY

Understanding the mechanisms responsible for the in situ generation of H₂ and its possible accumulation within asthenospheric reservoirs is essential for constraining the mantle hydrogen cycle and the processes that enable its migration toward shallower environments, such as the crust. Our group will develop experiments on such theme under high pressure and high temperatures. Experiments will be conducted in a 1000-ton toroidal belt apparatus that simulates mantle conditions at 5.5 GPa (~ 150 km depth) and temperatures from 900 °C to 1200 °C for 72 hours. The starting material is a homogeneous mixture of 80 wt.% fertile asthenospheric mantle (MPY) based on Ringwood pyrolite (Ringwood, 1962) and 20 wt.% eclogite (GA1) (Green et al., 1979). A double capsule technique will be employed, involving an inner gold capsule containing the sample and an outer iron capsule separated by a brucite [Mg(OH2)] buffer. The sample composition will be obtained by stoichiometric calculations and includes a combination of oxides (SiO₂, TiO₂, Al₂O₃, MnO, NiO, FeO, and Cr₂O₃) and carbonates (CaCO₃, MgCO₃, Na₂CO₃, and K₂CO₃). CO₂ will be generated during the experiment through the reaction of the carbonates. H2 will be generated by the reaction of the brucite buffer with the iron outer capsule. This configuration allows for control of O₂ fugacity (fO2) and molecular hydrogen generation. Previous research established that molecular hydrogen dissolves anisotropically in crystals, likely occupying interstitial positions (Yang et al., 2012), and that the quantity of dissolved H2 increases significantly as the conditions become more reducing (Hirschmann et al., 2012). However, its behavior in multi-phase systems remains fully constrained. This study aims to evaluate the partitioning of H2 between these coexisting phases (minerals and melt) under controlled conditions. The results will verify H2 compatibility in potential mantle reservoirs. providing crucial data on the deep hydrogen cycle, its connection to the crust, and sources of natural outgassing. These findings will significantly contribute to our knowledge of the role of H₂ in the properties of the upper mantle. Green, D. H., Jaques, L. A., & Hibberson, W. O. (1979). In The Earth: its origin, structure and evolution (pp. 265-300). Academic Press. Hirschmann, M. M., Withers, A. C., Ardia, P., & Foley, N. T. (2012). EPSL, 345, 38-48. Ringwood, A. E. (1962). A model for the upper mantle. Journal. of Geophysical. Research, 67(2), 857-867. Yang, X., Keppler, H., & Li, Y. (2016). Molecular hydrogen in mantle minerals. Geochemical Perspectives Letters, 2(2), 160-168.

  • Marum, Victor Jorge De Oliveira (Universidade Estadual de Campinas, Brazil): Archeointensity database and geomagnetic field reference curves for South America over the past 5 millennia

The study of variations in geomagnetic field intensity over time and space is crucial to understand the evolution of the geodynamo and its interactions with the Earth’s surface. In this work, we introduce the SAGEOMAG (South America GEOMAGnetic) database – a comprehensive and updated repository of geomagnetic field intensity records derived from archeological artifacts and volcanic materials over the past 5 millennia and adherent to the FAIR (Findable, Accessible, Interoperable e Reusable) principles. A key advantage of the SAGEOMAG database is the inclusion of statistical parameters at the specimen level for data quality control, as well as the data categorization according to the hierarchical level of record (site, fragment or specimen). Additionally, we propose new intensity references curves for South America (SARIC), modeled with a bootstrap algorithm that minimizes the influence of outliers and estimates the probability density function without needing explicit prior shape considerations. For records without intensity errors and age uncertainty details in the original studies, standard errors and uncertainties were assigned based on log-normal distributions. Our findings demonstrate that the modeling of master curves is highly sensitive to the quality filters applied to the data and the hierarchical level of the records. This study aims to improve the organization of geomagnetic data for South America and contribute to regional and global archeomagnetic field modeling, thereby enhancing our understanding of the geomagnetic field evolution and especially the South Atlantic Anomaly (SAA).

  • Mcdonough, William Francis (Tohoku Univesity, Japan): Earth’s composition: origin, energy budget, and insights from geoneutrinos

One in every two atoms in the Earth, Mars, and the Moon is oxygen; it is the third most abundant element in the solar system. The oxygen isotopic compositions of the terrestrial planets are different from those of the Sun and demonstrate that these planets are not direct compositional analogs of the solar photosphere. Likewise, the Sun’s O/Fe, Fe/Mg and Mg/Si values are distinct from those of inner solar system chondrites and terrestrial planets. These four elements (O, Fe, Mg, Si) make up 90\% to 94\% by mass (and atomic \%) of the rocky planets, and their abundances are determined uniquely using geophysical, geochemical, and cosmochemical constraints. The rocky planets likely grew rapidly (with $\tau_{accretion-ages}$ $\leq$\,10 million years) from large populations of planetesimals, most of which were differentiated, having a core and a mantle, before being accreted. Planetary growth in the early stages of protoplanetary disk evolution was rapid and was only partially recorded by the meteoritic record. The noncarbonaceous meteorites (NC) provide insights into the early history of the inner solar system and are used to construct a framework for how the rocky planets were assembled. NC chondrites have chondrule ages that are two to three million years younger than $t_{zero}$ (the age of calcium-aluminum inclusions, CAI), documenting that NC chondrites are middle- to late-stage products of solar system evolution. The composition of the Earth, its current form of mantle convection, and the amount of radiogenic power that drives its engine remain controversial topics. Earth’s dynamics are driven by primordial and radiogenic heat sources. Measurement of the Earth’s geoneutrino flux defines its radiogenic power and restricts its bulk composition. Using the latest data from the KamLAND and Borexino geoneutrino experiments affirms that the Earth has $\sim$\,20 TW of radiogenic power and sets the proportions of refractory lithophile elements in the bulk silicate Earth at $\sim$\,2.7 times that in CI chondrites. The bulk Earth and the bulk Mars are enriched in refractory elements about 1.9 times that of the CI chondrites. Earth is more volatile-depleted and less oxidized than Mars.

  • Melo, Janaína (USP, Brazil): Geological Interpretation of Data Augmentation Techniques Applied to Seismic Data Inversion Using Neural Networks

Determining accurate seismic velocity models is a challenging step in several geological and environmental applications, such as identifying sequestered carbon reservoirs, characterizing oil and gas reservoirs and estimating aquifer water storage capacity. With the advance of deep learning-based methods in seismic data processing, several approaches now use computer vision data augmentation techniques to overcome the limited availability of seismic data. These techniques artificially increase the size, variety, and complexity of training datasets, while preserving the semantic meaning of the images, regardless of the specific neural network model used. Some conventional data augmentation transformations (e.g. rotation, horizontal and vertical flip, and additive Gaussian noise) have been widely applied in geological fault detection, salt body mapping, seismic facies interpretation , and seismic velocity model reconstruction. These studies have shown that data augmentation strategies improve the accuracy and robustness of deep learning models and are more effective when applied to high-quality seismic data. Nevertheless, it remains unclear which augmentation transformations preserve the physical properties of the seismic wave field and accurately reflect the geological characteristics of the subsurface. This work aims to analyze the geological relevance of different data augmentation techniques used in seismic velocity model inference to contribute to our understanding of their role in seismic inversion. This procedure involves training and testing the improved InversionNet convolutional neural network with the 2D CurveVel-B acoustic synthetic seismic dataset from the OpenFWI platform. The results showed that the transformations of rotation, elastic transform, Gaussian noise, and Gaussian blur are consistent with the subsurface geological characteristics and the physical properties of the seismic data. In order to reconstruct high-quality velocity models, it is crucial to select low values for these transformation parameters to preserve the seismic signal’s signature and its original statistical distribution. Other results showed that horizontal and vertical flipping decreased the network’s performance. Vertical flipping is not recommended for seismic data inversion because it can result in information loss or physical inconsistencies in the transformed seismograms. Additionally, horizontal flipping is only suitable for velocity models that have laterally symmetric geological structures and exhibit horizontal invariance. In summary, it is important to carefully select the transformations and their respective parameters, as slight variations in the metrics can result in significant differences in velocity inference and geological structure mapping.

  • Miranda, Caetano Rodrigues (Instituto de Fisica da Universidade de Sao Paulo, Brazil): Computational Petrophysics: Integrating Multiscale Modeling and Synchrotron techniques for CO₂ Storage and planetary sciences

Understanding the fundamental processes governing CO₂ storage in geological formations is crucial for optimizing sequestration strategies, high-pressure geophysics, and planetary sciences. This work presents a multiscale modelling and experimental approach to investigate mineralization mechanisms in geological sites. By integrating density functional theory (DFT) calculations, molecular dynamics simulations, and lattice Boltzmann methods, we analyse fluid-mineral interactions from the nanoscale to the reservoir scale, mineral transformations, and their implications for seismic wave propagation. Advanced synchrotron techniques, including time-resolved X-ray tomography and fluorescence at Sirius-LNLS, provide experimental validation, enabling direct observation of mineral dissolution and precipitation under controlled conditions. Furthermore, virtual reality tools enhance the visualization and interpretation of complex petrophysical processes. This integrated framework bridges computational and experimental petrophysics, offering new insights into the monitoring, efficiency, and long-term stability of CO₂ mineral trapping in deep saline aquifers and contributing to advancing predictive models of mineral behaviour at extreme pressures and temperatures, with direct applications in geodynamic simulations, seismic interpretation, and planetary interiors research.

  • Monteiro E Silva, Mariana (Universidade de São Paulo, IAG-Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Brazil): Magmatism’s part on the formation of divergent continental margins: a numerical appproach

Passive continental margins, such as the Brazilian margins and their conjugate counterparts on the African continent, were formed through the divergent movement of large continental blocks. This progressive separation promoted the thinning of both the crust and the lithospheric mantle, a process that ultimately led to continental rupture and, subsequently, to the formation of new oceanic crust. Over the past decades, advances in computational modeling have enabled the development of codes capable of simulating the thermo-mechanical evolution of Earth’s interior. These models have successfully reproduced the formation and development of continental margins, helping to clarify their internal architecture, the mechanisms of subsidence, and the thermal behavior associated with post-rift cooling. Despite these advances, the explicit incorporation of magmatic processes into numerical models remains limited. Such processes are essential for understanding margins in which magmatism plays a significant role during continental breakup. Therefore, the present project aims to perform numerical simulations of the formation and evolution of divergent continental margins while integrating magmatic processes that occur simultaneously with lithospheric stretching. These processes are primarily attributed to the adiabatic decompression of the asthenospheric mantle as the lithospheric plates move apart. To develop these simulations, we will use the Mandyoc computational code, created by the Computational Geodynamics Group of the Department of Geophysics at IAG/USP and widely employed in large-scale thermo-mechanical studies. The results obtained will be applied to the understanding of magma-rich margins, with particular emphasis on the Pelotas Basin, located in the southern portion of the Brazilian margin, a region known for its expressive magmatic activity associated with the opening of the South Atlantic. The project also aims to quantify the volume of magmatism throughout geological time and compare it with the volume inferred from published data for these segments of the continental margin.

  • Nuñez, Andrés Genaro (Escuela politécnica nacional, Ecuador): Mineral identification and chemometric analysis using Raman spectra

This work presents the development of R-based algorithm for mineral identification and approximate chemical estimation from Raman spectra. The program integrates automated routines such as normalization, baseline correction, smoothing, peak detection, and full width at half maximum (FWHM) calculation. These steps provide standardized spectral processing and ensure reproducible results. The algorithm implements specific functions based on calibrations proposed in the literature for representative minerals (olivine, pyroxene, amphibole, and serpentine). It enables spectral comparison through Pearson correlation coefficients, peak-matching algorithms, and approximate chemical formula es- timation. The database includes more than 6,300 Raman spectra from the RRUFF library, ensuring broad coverage and robust performance in mineral recognition. Results indicate that the correlations obtained with this algorithm are com- parable to those produced by established tools such as CrystalSleuth, with a reduced error margin (±0.05). In addition, the processing time is significantly optimized, even when handling large datasets, which demonstrates both efficiency and scalability. In conclusion, the developed algorithm provides an accessible, fast, and reproducible tool for mineral identification and compositional estimation using Raman spectroscopy. Its design makes it a valuable complement to conventional analytical techniques, with potential applications in both academic research and geoscientific industry..

  • Paucar, Stalyn David (Universidad Central del Ecuador, Ecuador): Evidence of retrograde metamorphism in the El Oro Metamorphic Complex

The El Oro Metamorphic Complex, located in southwestern Ecuador, consists of different low- and high- grade metamorphic rocks. The evidence of retrograde metamorphism is studied through the bibliographic review, especially, of the results obtained in the El Oro Metamorphic Complex (1990-1993) as part of the Cordillera Real Project (1986-1993) and other recent papers. Evidence of retrograde metamorphism has been mentioned in the Quebrada Plata Unit from amphibolite to green schists facies and in the Raspas ophiolitic complex from eclogite to blue schists. In addition, petrographic evidence of retrograde metamorphism has been obtained in an eclogite block from La Chilca Unit. Also, retrograde metamorphism is described regarding the evolution of the metamorphic complex (Quebrada Plata Unit), the exhumation processes, associated geological structures and mineral reactions.

  • Pinheiro, Pedro Evangelista (Universidade de São Paulo, Brazil): Numerical Simulation of Tectonic Styles

The internal structure of rocky planets is composed of geological layers with distinct rheologies. The composition, temperature, and viscosity of the material directly influence the deformational behavior of rocks. Efficient heat-transfer and mass-transport processes such as convection occur in the asthenosphere due to its low-viscosity ductile rheology. In contrast, the low temperatures in the lithosphere make it viscous and rigid. Thus, the dynamics of the upper mantle in several rocky bodies of the Solar System are governed by an asthenospheric convection system beneath a viscous, immobile lithosphere, known as the ‘stagnant-lid’ regime. Earth is a particular case in which a very narrow combination of factors enables plate tectonics—a phenomenon in which the lithosphere is fragmented and mobilized by subduction into the asthenospheric mantle, while new lithosphere is produced by magmatism. To analyze the physical and rheological conditions that contribute to the development of different tectonic styles, this study aims to conduct numerical simulations of the plate-tectonic regime, the stagnant-lid regime, and other possible transitional states between these systems. The numerical model Mantle Dynamics Simulator Code, developed at the Department of Geophysics of the Institute of Astronomy, Geophysics, and Atmospheric Sciences of the University of São Paulo, was used to reproduce the dynamics and thermal evolution of the upper mantle. The simulations record the evolution of temperature, viscosity, velocities, and deformation fields throughout the modeled scenario. Rheological properties of wet olivine derived from laboratory experiments were applied in viscoplastic rheology models. As a result, stagnant-lid, plate-tectonic, and transitional tectonic styles were successfully reproduced numerically. The simulations exhibit features consistent with the internal dynamics of rocky planets, such as asthenospheric convection, subduction, and the formation of lithospheric plates. Variations in lithospheric strength and model viscosity parameters were determining factors in the evolution of the different tectonic styles. [Grant nº 2024/03399-6, São Paulo Research Foundation (FAPESP)].

  • Rodrigues, Laís Nathalia (Instituto de Astronomia, Geofisica e Ciências Atmosféricas, Brazil): Tomography of Absolute and Relative P-Wave Travel-Time Anomalies for the Determination of Radial and Azimuthal Anisotropy in South America.

Seismic anisotropy is a powerful tool for investigating upper mantle deformation, as it directly reflects the deformational processes occurring within the Earth. Common methods to estimate anisotropic structures in the crust and mantle include body-wave and surface-wave tomography, receiver functions, and shear-wave splitting measurements. Among these, P-wave anisotropic tomography is relatively new, having been fully developed and applied only in the last decade, enabling 3-D imaging of P-wave anisotropy in the crust and upper mantle. In this PhD project, we first tested the tomography code using a synthetic model simulating a subducting lithospheric plate, in order to evaluate its limitations. We then applied the method to the Paraná Basin using relative travel-time residuals from manual picks of local and teleseismic events, combined with high-frequency travel-time anomalies from the ISC-EHB catalog, to improve model resolution. Seismic station coverage in Brazil has significantly increased since 2011, with the installation of permanent and temporary networks in the Paraná (PB), Chaco-Paraná (CB), and Pantanal (PtB) basins, providing unprecedented conditions to perform, for the first time, a P-wave anisotropy tomography study in South America. Our main objective is to investigate the mechanical coupling between the crust and lithospheric mantle, as well as between the lithosphere and asthenosphere, in a structurally complex region that encompasses cratonic roots, orogenic belts, magmatic provinces, and sedimentary basins. By combining radial and azimuthal anisotropy maps at different depths with a new isotropic P-wave velocity model, we aim to provide new constraints on large-scale deformation signatures that shaped the lithospheric structure of South America and to contribute to a better understanding of its tectonic evolution.

  • Santos Rego, Jessica (University of São Paulo (USP), Brazil): Exploring the thermoelasticity of high-pressure SiO2 phases

Silica (SiO₂) exhibits a notably complex phase diagram, characterized by several high-pressure polymorphs, whose structural transformations govern the mineral’s elastic, thermodynamic, and vibrational behavior under deep-Earth conditions. Among these polymorphs, the transitions between stishovite, CaCl₂-type, and seifertite are central to understanding how silica responds to extreme pressure–temperature environments relevant to the lower mantle. Accurately capturing the behavior of these phases requires accounting for anharmonic effects, which strongly influence phase stability, elastic softening, and the evolution of thermoelastic properties. Traditional ab initio approaches, often constrained by the quasiharmonic approximation, tend to underestimate these effects, leading to uncertainties in the predicted high-temperature behavior of silica. To overcome these limitations, we develop a machine-learning interatomic potential using the DeePMD-kit framework, trained on an extensive and carefully curated DFT dataset generated with the r²SCAN meta-GGA functional. The dataset spans a wide P–T space and includes high-pressure crystalline configurations that capture the essential distortions and bonding environments of the silica polymorphs. This enables the model to reproduce anharmonic features that are inaccessible to simpler theoretical treatments. Using the resulting potential, we perform large-scale molecular dynamics simulations to model anharmonic vibrational behavior explicitly. Temperature-dependent elastic constants are determined using the stress-fluctuation formalism, providing access to elastic responses well beyond the quasiharmonic regime. This allows us to explore how elasticity evolves across phase transitions at conditions representative of the deep mantle. Overall, this work establishes a robust and efficient computational framework for quantifying the thermoelastic properties of silica under extreme conditions. By incorporating anharmonicity directly through machine-learning molecular dynamics, the approach significantly improves our ability to model mineral behavior in the deep Earth with greater physical realism.

  • Tartaglia, Rodolfo (Brazilian Center for Research in Energy and Materials – Brazilian Synchrotron Light Laboratory, Brazil): Extreme methods of analysis (EMA) beamline: Current status and Future Goals

A deep understanding of the physical properties of materials requires investigating them under diverse thermodynamic conditions. Submitting them to extreme conditions of pressure, temperature, and magnetic fields can also reveal novel phases of matter that are inaccessible at ambient conditions. Moreover, depending on how extreme these conditions are, such experiments can simulate unreachable environments as those found in the interiors of planets and stars. In this context, fourth-generation synchrotron facilities are crucial, as they can provide focused x-ray beams with high photon flux. This enables the investigation of electronic, structural, and magnetic properties through a wide range of techniques compatible with those sample environments. The combination of these conditions at synchrotron facilities has already led and continues to lead to the discovery of novel physical phenomena important in many fields of knowledge, including condensed matter physics, chemistry, materials science, and geosciences. Within this context, the EMA (Extreme Methods of Analysis) beamline at the Brazilian synchrotron light source Sirius was designed to provide a versatile infrastructure for high-resolution x-ray absorption spectroscopy, x-ray diffraction, and coherent diffraction imaging of samples subjected to extreme thermodynamic conditions. The beamline delivers high photon flux and focused beam sizes down to ~1×1 µm² in the hard x-ray energy range, enabling studies with exceptional spatial resolution. These capabilities are compatible with a broad range of sample environments, including megabar pressures, both high and low temperatures (from 300 mK to 5000 K), and magnetic fields up to 11 T. In the poster, I will present the current status of the EMA beamline and highlight some recent scientific results. I will also outline our plans to upgrade the current experimental setup, including a new sample-positioning stage and improvements to the laser-heating capabilities.

  • Timrov, Iurii (Paul Scherrer Institute, Switzerland): Advanced first-principles modeling of transition-metal compounds using extended Hubbard functionals
  • Tolotti, Caroline (universidade federal do rio grande do sul, Brazil): Volatiles, Eclogite, and Mantle Metasomatism Across the Subcontinental Lithosphere–Asthenosphere Boundary

The speciation of volatiles in the C–O–H system is tightly controlled by oxygen fugacity (fO₂), itself governed by redox reactions occurring within specific pressure–temperature fields. Although thermodynamic models provide essential insights, they often simplify the complexity of natural systems. High-pressure and high-temperature experiments offer a more realistic approach by reproducing compositionally complex mantle environments and testing the physicochemical behavior of volatiles under controlled conditions. This study experimentally investigates how C–O–H volatiles influence mineral formation and mantle melting, as well as how these volatiles are stored in solid phases and released as fluids or gases at the lithosphere–asthenosphere interface of the cratonic subcontinental mantle. Experiments are conducted at pressures from 2.5 to 10 GPa to simulate deep mantle conditions relevant to metasomatic and melting processes. This approach provides key constraints for modeling mantle reactivity, supports petrogenetic interpretations of natural rocks, and contributes to the assessment of natural volatile reservoirs.

  • Wentzcovitch, Renata (Columbia University, United States): Fe2+ partitioning in Al-free pyrolite: consequences for seismic velocities and heterogeneities

Iron partitioning among the main lower mantle phases, bridgmanite (Bm) and ferropericlase (Fp), has non-monotonic behavior owing to the high-spin to low-spin crossover in ferrous iron (Fe2+) in Fp. Results of previous studies of the iron partitioning coefficient between these phases, K_D, still have considerable uncertainty. Here, we investigate the Fe2+ partitioning behavior using well-documented ab initio free energy results plus new updates. Although we focus on Fe2+ only, we describe the effect of this iron spin crossover (ISC) on K_D and of the latter on compositions and seismic velocities in a pyrolitic aggregate. Our results suggest that its velocities are mainly affected by the ISC and less so by the Fe2+ partitioning. In contrast, iron partitioning manifests in thermally induced velocity heterogeneity ratios. Prediction of the seismological parameter R_(S/P) (∂lnV_S/∂lnV_P) including iron partitioning effects resembles quantitatively R_(S/P)’s inferred from several tomographic studies down to 2,400 km depth.

Venue

Venue: The event will be held at IFT-UNESP, located at R. Jornalista Aloysio Biondi, 120 – Barra Funda, São Paulo. The easiest way to reach us is by subway or bus, See arrival instructions here.

Accommodation: Participants whose accommodation will be provided by the institute will stay at Hotel Intercity the Universe Paulista. Hotel recommendations are available here.

Attention! Some participants in ICTP-SAIFR activities have received email from fake travel agencies asking for credit card information. All communication with participants will be made by ICTP-SAIFR staff using an e-mail “@ictp-saifr.org”. We will not send any mailings about accommodation that require a credit card number or any sort of deposit. Also, if you are staying at Hotel Intercity the Universe Paulista, please confirm with the Uber/Taxi driver that the hotel is located at Rua Pamplona 83 in Bela Vista (and not in Jardim Etelvina).

Additional Information

BOARDING PASS: All participants, whose travel has been provided or will be reimbursed by ICTP-SAIFR, should bring the boarding pass  upon registration. The return boarding pass (PDF, if online check-in, scan or picture, if physical) should be sent to secretary@ictp-saifr.org by e-mail.

Visa information: Nationals from several countries in Latin America and Europe are exempt from tourist visa. Nationals from Australia, Canada and USA are required to apply for a tourist visa.

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