A detailed understanding of the stress state and variable geomechanical properties (frictional strength, Young's modulus, etc.) of the Earth's crust are important parameters for lithosphere dynamics as well as engineering applications related to the extraction, transport, storage and disposal of energy or materials.
In the context of lithosphere mechanics, the strength limits are bounded by two end-members. In one end-member model, the crust is strong and fails at high differential stresses (hundreds of MPa) consistent with the classical Christmas tree envelope and static friction governed by Byerlee's law. In the other end-member model, the crust is weak and fails at low differential stresses (tens of MPa) consistent with stress magnitudes that may result from topographic loading and tectonic forces. How significant are these end-member scenarios and how do they affect our perception of lithosphere dynamics on time scales ranging from a single earthquake to long-term processes such as orogeny? Can the end-members be reconciled or are they mutually exclusive? Do they reflect differences between continental interiors and plate margins or tectonically inactive and active regions?
Geomechanics is focused on providing the most accurate estimate of the present-day stress state, or quantifying criticality in the context of subsurface use. More complex questions can be addressed with numerical models. But how can the uncertainties of model parameters (material properties and structures) and calibration data (stress magnitudes) be quantified?
To address these fundamental questions, we invite contributions from observational, experimental, theoretical, and numerical studies that improve our understanding of the crustal stress state or expand the methodological repertoire. Highly appreciated are presentations about new methods and on strategies to reduce the uncertainties.

Microstructures play a fundamental role in deciphering the rheology of the lithosphere and lithospheric tectonics. Microstructures and crystallographic textures are used to analyze the physical and chemical properties of geomaterials, while deformation microstructures (e.g., fabrics, textures, grain sizes, shapes, cracks, etc.) can be used to infer, identify, and quantify deformation, metamorphic, magmatic or diagenetic processes. Processes such as grain-size reduction, metamorphic reactions, crack growth, and the development of crystallographic preferred orientations modify the rheological properties of rocks and minerals, providing key information on the dynamics of small- to large-scale tectonic processes. In this session, we invite contributions that use microstructure and texture analyses from field observations, laboratory experiments, and numerical modelling at brittle and/or ductile conditions aiming to constrain deformation mechanisms.

The session aims at making the point on our understanding of the relationships between the development of folds and fault zones, the mechanisms and history of rock strain acquisition from the macroscopic to the microscopic scales, the orientations and magnitudes of stresses and the fluids that flowed within the rocks and interacted with them. We invite contributions covering these aspects, from field-based case studies to modeling.

Reactions between fluids and rocks have a fundamental impact on many of the natural and geo-engineering processes across a wide range of scales. At the nano- and micro-scale, these processes can be recorded by the formation of natural patterns in rocks, such as the dendritic patterns, banding patterns, crack patterns, mineralogical replacement, growth patterns or deformation patterns. The visible regularity of pattern structures or textures elucidates the physio-chemical environment during fluid-rock interactions. At the meso- and macro-scale, such processes manifest in localization of deformation, earthquake nucleation caused by high pressure fluid pulses, as well as metamorphic reactions and rheological weakening triggered by fluid flow, metasomatism and fluid-mediated mass transport. Moreover, the efficiency of many geo-engineering processes is partly dependent on fluid-rock interactions, such as hydraulic fracturing, geothermal energy recovery, CO2 storage and wastewater injection. All our observations in the rock record are the end-product of all metamorphic, metasomatic and deformation changes that occurred during the interaction with fluid. Therefore, to investigate and understand these complex and interconnected processes, it is required to merge knowledge and techniques deriving from several disciplines of the geosciences.
We invite multidisciplinary contributions that investigate fluid-rock interactions throughout the entire breadth of the topic, using fieldwork, microstructural and petrographic analyses, geochemistry, experimental rock mechanics, thermodynamic modeling and numerical modeling.

The goal of this session is to reconcile short-time/small-scale and long-time/large-scale observations, including geodynamic processes such as subduction, collision, rifting, or mantle lithosphere interactions. Despite the remarkable advances in experimental rock mechanics, the implications of rock-mechanics data for large temporal and spatial scale tectonic processes are still not straightforward, since the latter are strongly controlled by local lithological stratification of the lithosphere, its thermal structure, fluid content, tectonic heritage, metamorphic reactions, and deformation rates.

Mineral reactions have mechanical effects that may result in the development of pressure variations and thus are critical for interpreting microstructural and mineral composition observations. Such effects may fundamentally influence element transport properties and rheological behavior.
Here, we encourage presentations focused on the interplay between metamorphic processes and deformation on all scales, on the rheological behavior of crustal and mantle rocks, and time scales of metamorphic reactions in order to discuss
(1) how and when up to GPa-level differential stress and pressure variations can be built and maintained at geological timescales and modeling of such systems,
(2) deviations from lithostatic pressure during metamorphism: fact or fiction?
(3) the impact of deviations from lithostatic pressure on geodynamic reconstructions.
(4) the effect of porous fluid and partial melting on the long-term strength.
We, therefore, invite the researchers from different domains (rock mechanics, petrographic observations, geodynamic and thermo-mechanical modeling) to share their views on the way forward for improving our knowledge of the long-term rheology and chemo-thermo-mechanical behavior of the lithosphere and mantle.

The recent methodological and instrumental advances in paleomagnetism, micromagnetic modelling, and magnetic fabric research further increased their already high potential in solving geological, geophysical, and tectonic problems. Integrated paleomagnetic and magnetic fabric studies, together with structural geology and petrology, are very efficient tools in increasing our knowledge about sedimentological, tectonic or volcanic processes, both on regional and global scales. This session is intended to give an opportunity to present innovative theoretical or methodological works and their direct applications in various geological settings. Especially welcome are contributions combining paleomagnetic and magnetic fabric data, integrating various magnetic fabric techniques, combining magnetic fabric with other means of fabric analysis, or showing novel approaches in data evaluation and modelling. We also highly solicit contributions showing all aspects of paleomagnetic reconstructions, acquisition of characteristic remanence and remagnetisations applied to solving geotectonic problems. We also solicit contributions that (i) take advantage of recent advances in imaging magnetic behaviour at the grain-scale; (ii) present paleomagnetic challenges that could be solved using newly available methods; and/or (iii) use micromagnetic modelling to characterize the behaviour of magnetic carriers.

Imaging and characterization of both seismogenic structures and elastic/anelastic properties of the surrounding medium play a key role in the understanding of the deformation processes from regional to small scale. The presence of fluids and crustal heterogeneity makes analysis by geophysical methods challenging. In these conditions, fluids interact with seismic sources caused by deformation, affecting the genesis and growth of seismic sequences. Nowadays also for many green energy applications, it is crucial to comprehend the geometry and kinematics of crustal-scale faults from field measurements (e.g., geothermal energy, CO2 storage, mining for minerals important for battery production) with the goal of minimizing the related risks to geo-resources exploitation.

This session is designed to propose a discussion about cutting-edge seismic techniques with the aim of imaging and characterizing seismically active and ancient faults in tectonic and volcanic areas. Contributions to the session may include challenging applications, where the joint inversion of both active and passive seismic data are employed to shed light on not-straightforward complexities in different geological contexts, even integrated by the results derived from other geophysical investigations.

We welcome contributions from velocity tomography, attenuation tomography (coda, t* method, direct wave attenuation), source imaging and characterization (absolute and relative location techniques, focal mechanism and stress drop analysis, receiver functions), active-source seismic techniques (reflection, refraction, integrated drilling data, seismic attributes), along with multidisciplinary studies. As a final issue, other geophysical data (e.g. potential methods like gravimetric, magnetic, or geo-electric studies) could also provide further helpful information, to better constrain the interpretation of seismological data. We particularly encourage contributions from early-career researchers and those using novel techniques (e.g., data mining and machine learning).

Fibre optic based techniques allow probing highly precise direct point and distributed sensing of the full ground motion wave-field including translation, rotation and strain, and environmental parameters such as temperature and even chemicals at a scale and to an extent previously unattainable with conventional geophysical methods. Considerable improvements in optical and atom interferometry enable new concepts for inertial rotation, translational displacement and acceleration sensing. Laser reflectometry using both fit-to-purpose and commercial fibre optic cables have successfully detected a variety of signals including microseism, local and teleseismic earthquakes, volcanic events, ocean dynamics, etc. Significant breakthrough in the use of fibre optic sensing techniques came from the new ability to interrogate telecommunication cables at high precision both on land and at sea, as well as in boreholes and at the surface. Applications of the resulting new type of data are manifold: they include seismic source and wave-field characterization with single point observations in harsh environments like active volcanoes, the ocean bottom, the correction of tilt effects, e.g. for high performance seismic isolation facilities, as well as seismic ambient noise interferometry and seismic building monitoring.

We welcome contributions on developments in instrumental and theoretical advances, applications and processing with fibre optic point and/or distributed multi-sensing techniques, light polarization and transmission analyses, using standard telecommunication and/or engineered fibre cables. We seek studies on theoretical, observation and advanced processing in fields, including seismology, volcanology, glaciology, geodesy, geophysics, natural hazards, oceanography, urban environment, geothermal applications, laboratory studies, large-scale field tests, planetary exploration, gravitational wave detection, fundamental physics. We encourage contributions on data analysis techniques, machine learning, data management, instrumental performance and comparison as well as new experimental, field, laboratory, modeling studies in fibre optic sensing studies.

We are happy to announce Prof. Martin Landrø, Prof. Kuo-Fong Ma and Dr. David Sollberger as invited speakers!

A predictive knowledge of fault and fracture zones and their transmissibility can have an enormous impact on the viability of geothermal, carbon capture, energy and waste storage projects. Understanding the role and the effects played by fault and fracture zones, physical properties of the system (e.g. frictional strength, cohesion and permeability) on the in-situ fluid behaviour can generate considerable advantages during exploration and management of these reservoirs and repositories. Generating realistic models of the subsurface requires detailed information on the deformation processes, structure and properties of fault and fracture zones. To create accurate and realistic models, we need to characterise the geometry and the distribution of faults and fractures, as well as the mechanical and petrophysical properties of the fractured rocks. The properties and the evolution of faulted/fractured rocks can be evaluated using a combination of laboratory data, well data and outcrop analogues which then constitute the backbone of discrete fracture network (DFN) modelling and robust numerical flow models.

We encourage researchers on applied or interdisciplinary energy studies associated with low carbon technologies (geothermal, repositories, hydrogeology, CCS) and modelling of fractured media (e.g. DFN) to come forward for this session. We look forward to interdisciplinary studies which use a combination of methods to analyse rock deformation processes and the role of faults and fractures in subsurface energy systems, including but not restricted to outcrop studies, laboratory measurements, analytical methods and numerical modelling. We are also interested in studies working across several different scales and that try to address the knowledge gap between laboratory scale measurements and reservoir scale processes.

Earthquake mechanics is controlled by a spectrum of processes covering a wide range of length scales, from tens of kilometres down to few nanometres. The geometry of the fault/fracture network and its physical properties control the global stress distribution and the propagation/arrest of the seismic rupture. At the same time, earthquake rupture nucleation, rupture and arrest are governed by fracture propagation and frictional processes occurring within extremely localized sub-planar slipping zones. The co-seismic rheology of the slipping zones themselves depends on deformation mechanisms and dissipative processes active at the scale of the grain or asperity. The study of such complex multiscale systems requires an interdisciplinary approach spanning from structural geology to seismology, geophysics, petrology, rupture modelling and experimental rock deformation. In this session we aim to convene contributions dealing with different aspects of earthquake mechanics at various depths and scales such as:

- the thermo-hydro-mechanical processes associated with co-seismic fault weakening based on rock deformation experiments, numerical simulations and microstructural studies of fault rocks;
- the study of natural and experimental fault rocks to investigate the nucleation mechanisms of intermediate and deep earthquakes in comparison to their shallow counterparts;
- the elastic, frictional and transport properties of fault rocks from the field (geophysical and hydrogeological data) to the laboratory scale (petrophysical and rock deformation studies);
- the internal architecture of seismogenic fault zones from field structural survey and geophysical investigations;
- the modeling of earthquake ruptures, off-fault dynamic stress fields and long-term mechanical evolution of realistic fault networks;
- the earthquake source energy budget and partitioning between fracture, friction and elastic wave radiation from seismological, theoretical and field observations.
- the interplay between fault geometry and earthquake rupture characteristics from seismological, geodetic, remote sensed or field observations;

We particularly welcome novel observations or innovative approaches to the study of earthquake faulting. Contributions from early career scientists are solicited.

Waves in the Earth’s crust are often generated by fractures in the process of their sliding or propagation. Conversely, the waves can trigger fracture sliding or even propagation. The presence of multiple fractures makes geomaterials non-linear. Therefore the analysis of wave propagation and interaction with pre-existing or emerging fractures is central to geophysics. Recently new observations and theoretical concepts were introduced that point out to the limitations of the traditional concept. These are:
• Multiscale nature of wave fields and fractures in geomaterials
• Rotational mechanisms of wave and fracture propagation
• Strong rock and rock mass non-linearity (such as bilinear stress-strain curve with high modulus in compression and low in tension) and its effect on wave propagation
• Apparent negative stiffness associated with either rotation of non-spherical constituents or fracture propagation and its effect on wave propagation
• Triggering effects and instability in geomaterials
• Active nature of geomaterials (e.g., seismic emission induced by stress and pressure wave propagation)
• Non-linear mechanics of hydraulic fracturing
• Synchronization in fracture processes including earhtquakes and volcanic activity

Complex waves are now a key problem of the physical oceanography and atmosphere physics. They are called rogue or freak waves. It may be expected that similar waves are also present in non-linear solids (e.g., granular materials), which suggests the existence of new types of seismic waves.

It is anticipated that studying these and related phenomena can lead to breakthroughs in understanding of the stress transfer and multiscale failure processes in the Earth's crust, ocean and atmosphere and facilitate developing better prediction and monitoring methods.

The first part of the session is designed as a forum for discussing these and relevant topics.

The second part of the session aims to nurture the development of fractals, multifractals and related nonlinear methodologies applicable to a wide range of hydrological, meteorological systems and their multiscale interactions. Theories considering scalar and vector fields, applications in the area of hydrometeorology (e.g. rainfall extremes, urban flood control, water management etc.), analysis of in-situ, remotely sensed data and simulation techniques are of interest.

The session focuses on research aimed at defining the geometry, kinematics, and associated stress- and deformation fields of active faults, as well as building up tectonic and seismotectonic models, in all tectonic regimes, including volcanic areas. Assessing the geometry and kinematics of faults, key to seismic hazard assessment, can be often challenging due to the possible paucity of quantitative data, both at the near-surface and at seismogenic depths.
Tackling this challenging issue is nowadays possible by combining data from different approaches and disciplines, with the aim of obtaining a more detailed characterization/imaging of single active faults, as well as reliable seismotectonic models. In addition, technological advances in data collection and analysis provide a significant contribution. As an example, photogrammetry and LIDAR-derived models enable collecting a great deal of geological data even in inaccessible areas; these data can then be integrated with field (structural), seismological and geophysical data with the purpose of a better understanding of active faults geometry. Also, the improvement in data processing allows to enhance seismic catalogues in areas with low-level seismicity, as well as collect new and more detailed data from geophysical, geodetic, or remote-sensing analysis.
Contributions dealing with the following topics are welcome: i) active faults, including volcanic areas; ii) classical to innovative multiscale and multidisciplinary geological, seismological and geophysical approaches; iii) new or revised seismological, geophysical, field-and remotely-collected datasets; iv) faults imaging, tectonic-setting definition and seismotectonic models; v) numerical and analogue modelling.

Active faults in slow deforming areas (<5mm/yr) constitute a critical hazard for the population not only because they are capable of eventually generating large destructive earthquakes but especially because their longer recurrences negatively impact the social perception of the risk. The characterization of fault systems in these areas is intrinsically more challenging as surface processes may mask the rates of tectonic activity and/or the deformation is diffusely distributed. Ultimately, this can prevent having a proper age control of the faults’ activity histories. In recent years, overcoming these issues has implied adapting and combining multiple known methodologies developed for faster faults to these new settings (e.g., multi-site paleoseismological trenching, tectonic geomorphology, structural analysis), as well as developing new modeling tools to approximate fault behavior when field data is scarce or takes a long time to gather (e.g., physics-based modeling, geodetic data). The characterization of fault activity in terms of earthquake occurrence and slip rate, together with the proper treatment of their uncertainties, is of vital relevance for probabilistic seismic and fault-displacement hazard assessments of these regions (PSHA and PFDHA). In addition, active faults of slow deforming settings are critical to evaluate the site-specific seismic hazard for critical facilities (e.g., power plants or dams), as longer recurrence times must be considered.

This session is an opportunity to discover and share new data, advances and approaches of the research focused on characterizing seismogenic faults and their activity in slow deformation settings worldwide. We aim our session to enhance discussion about the future actions in this matter, also among early career scientists and scientific communities like the Fault2SHA working group. Hereby, we invite contributions from various fields including paleoseismology, geomorphology, geodesy, structural analysis, tectonic geochronology, numerical modeling, as well as fault-based PSHA and PFDHA studies.

Since approximately 90% of the seismic moment released by earthquakes worldwide occurs near subduction zones, it is crucial to improve our understanding of seismicity and the associated seismic hazard in these regions. Seismicity in subduction zones takes many forms, ranging from relatively shallow seismicity on outer-rise and splay faults and the megathrust to intermediate-depth (70-300 km) and deep events (>300 km). While most research on subduction earthquakes focuses on the megathrust, all of these different seismic environments contribute to the seismic budget, hazard and broad dynamics of a subduction zone.

This session aims to integrate our knowledge on different aspects of subduction zone seismicity to improve our understanding of the interplay between such events and their relationship to subduction dynamics. We particularly invite abstracts that use geophysical and geological observations, laboratory experiments and/or numerical models to address questions such as: (1) What are the mechanisms behind intraplate seismicity? (2) How do outer-rise and splay fault seismicity relate to the seismogenic behaviour of the megathrust? (3) How do slab dynamics influence and potentially link both shallow and deep seismicity?

During the last decades, methods have significantly improved in geophysics, geodesy, and in paleoseismology-geomorphology. Hence, on one hand the number of earthquakes with well-documented rupture process and deformation pattern has increased significantly. On the other hand, the number of studies documenting long time series of past earthquakes, including quantification of past deformation has also increased. In parallel, the modeling community working on rupture dynamics, including earthquake cycle is also making significant progresses. Thus, this session is the opportunity to bring together these different contributions to foster further collaboration between the different groups focusing all on the same objective of integrating earthquake processes into the earthquake cycle framework. In this session we welcome contributions documenting earthquake ruptures and processes, both for recent or ancient events, from seismological, geodetic, or paleoseismological perspective. Contributions documenting deformation during pre-, post-, or interseismic periods, which are highly relevant to earthquake cycle understanding, are also very welcomed. Finally, we seek for any contribution looking at the earthquake cycle from the modeling perspective, especially including approaches mixing data and modeling.

Deformation zones and faulting processes develop in several geodynamic environments, involving deep and/or shallow crust. In active tectonics contexts, either if they are in subarea or subaqueous environments, unravelling the faults’ long-term evolution has a crucial impact for seismic and tsunami hazard assessment. In case of subaqueous environments, over the last years, new geological and geophysical instrumentation has made possible the acquisition data with unprecedented detail and resolution, providing for a better definition of offshore fault systems and seismic parameter calculations. Moreover, multiple parameters are expected to control fault evolution, such as the tectonic and geodynamic setting, erosion, the amount of sediments deposited on the hanging wall, fluids circulation, or lithology. While the effects of some of these parameters are well established, many others are still poorly constrained by actual data.
This session aims to better define the properties of faults and deformation zones, and to understand how their characteristics change over time. At the same time, this session also aims to compile studies that focus on the use of geological and geophysical data to identify subaqueous active structures, attempting to quantify the seafloor deformation, evaluating their seismogenic and tsunamigenic hazards. We invite contributions dealing with faulting and deformation processes (normal, reverse and strike-slip) worldwide, in different geodynamic contexts, from the scale of the outcrops to mountain ranges, from offshore to lakes, and from the long-term to single seismic events. Since a multidisciplinary approach is the key to deep understanding, studies providing new perspectives and ideas in subaqueous active tectonics or involving diverse methods such as field-data analysis, paleoseismic trenching, stable isotopes, low temperature thermochronology, syn-kinematic U/Pb dating, cosmogenic exposure dating, petrographic analysis, or analogue/numerical modelling are welcome.

Tectonic faults accommodate plate motion through various styles of seismic and aseismic slip spanning a wide range of spatiotemporal scales. Understanding the mechanics and interplay between seismic rupture and aseismic slip is central to seismotectonics as it determines the seismic potential of faults. In particular, unraveling the underlying physics controlling these styles of deformation bears a great deal in earthquakes hazards mitigation especially in highly urbanized regions. We invite contributions from observational, experimental, geological and theoretical studies that explore the diversity and interplay among seismic and aseismic slip phenomena in various tectonic settings, including the following questions: (1) How does the nature of creeping faults change with the style of faulting, fluids, loading rate, and other factors? (2) Are different slip behaviors well separated in space, or can the same fault areas experience different failure modes? (3) Is there a systematic spatial or temporal relation between different types of slip?

The Eastern Mediterranean is an actively deforming region where three major tectonic plates interact: the African, the Arabian and the Eurasian plates. The Cenozoic geodynamic framework of the Eastern Mediterranean region consists of subduction, collision, strike-slip kinematics, extrusion of crustal blocks and slab deformation.

This session focuses on three aspects of the Eastern Mediterranean geodynamics:
(1) Which geodynamic mechanisms define the key active structures and how do they operate?
(2) How is surface deformation being accommodated over a range of temporal and spatial scales? How individual earthquakes accrue on faults to account for their long-term kinematics? Which is the impact of deep-seated processes on surface deformation?
(3) How did the geodynamic evolution through the Cenozoic lead to present day tectonic deformation?

We welcome contributions from a wide range of disciplines including, but not limited to, neotectonics, seismology, tectonic geodesy (e.g. GNSS, InSAR), paleoseismology, tectonic geomorphology, remote sensing, structural geology, and geodynamic modeling.

We strongly encourage the contribution of early career researchers.

A detailed understanding of earthquake processes plays a significant role in evaluating seismic hazard. Hence, it is crucial to unravel the mechanisms and conditions of rock failure, and the interplay between mineral- and tectonic-scale processes. In nature as well as in the laboratory, seismic ruptures have been observed fossilized as pseudotachylytes (i.e. solidified melt along coseismic faults), which does not exclude alternative processes in the case of ruptures that would not require melting (e.g. thermal pressurization in fluid-rich fault zones). Key information can be extracted from off-fault damage, including micro-scale fracturing of mineral grains, heat-induced transformations, and cyclic switches between brittle and ductile deformation. Several processes have been suggested to trigger mechanical instabilities and/or favor rupture growth, such as fluid percolation events, stress amplifications due to mineral reactions or geometrical complexities, but also grain size reduction, thermal runaway, or variations in strain rate.
While observational methods help image mechanical instabilities, laboratory experiments provide insights into the physics of the lubrication processes enabling seismic faults to grow under pressure. This session aims at facilitating transdisciplinary scientific discussions between all schools of research that address rock failure or related processes from the shallow crust down to the bottom of the upper mantle. We aim to consider and distinguish all stages of the rupture process (trigger, nucleation, propagation, and arrest) from crystals to tectonic plates. This session brings together contributions from various disciplines, including field geology, experimental geophysics, petrology, mineral physics, thermodynamics, seismology, and numerical modelling to discuss how, why, and when rocks break (or not).

Earthquake disaster mitigation involves different elements, concerning identification, assessment and reduction of earthquake risk. Each element has various aspects: a) analysis of hazards (e.g. physical description of ground shaking) and its impact on built and natural environment, b) vulnerability and exposure to hazards and capacity building and resilience, c) long-term preparedness and post-event response. Due to the broad range of earthquake disaster mitigation various seismic hazard/risk models are developed at different time scales and by different methods, heterogeneous observations are used and multi-disciplinary information is acquired.
We welcome contributions about different types of seismic hazards research and assessments, both methodological and practical, and their applications to disaster risk reduction in terms of physical and social vulnerability, capacity and resilience.
This session aims to tackle theoretical and implementation issues, as well as aspects of communication and science policy, which are all essential elements towards effective disasters mitigation, and involve:
⇒ the development of physical/statistical models for the different earthquake risk components (hazard, exposure, vulnerability), including novel methods for data collection and processing (e.g. statistical machine learning analysis)
⇒ earthquake hazard and risk estimation at different time and space scales, verifying their performance against observations (including unconventional seismological observations);
⇒ time-dependent seismic hazard and risk assessments (including contribution of aftershocks), and post-event information (early warning, alerts) for emergency management;
⇒ earthquake-induced cascading effects (e.g. landslides, tsunamis, etc.) and multi-risk assessment (e.g. earthquake plus flooding).
The interdisciplinary session promotes knowledge exchange, sharing best practices and experience gained by using different methods, providing this way opportunities to advance our understanding of disaster risk in "all its dimensions of vulnerability, capacity, exposure of persons and assets, hazard characteristics and the environment", while simultaneously highlighting existing gaps and future research directions.

Earthquake swarms are characterized by a complex temporal evolution and a delayed occurrence of the largest magnitude event. In addition, seismicity often manifests with intense foreshock activity or develops in more complex sequences where doublets or triplets of large comparable magnitude earthquakes occur. The difference between earthquake swarms and these complex sequences is subtle and usually flagged as such only a posteriori. This complexity derives from aseismic transient forcing acting on top of the long-term tectonic loading: pressurization of crustal fluids, slow-slip and creeping events, and at volcanoes, magmatic processes (i.e. dike and sill intrusions or magma degassing). From an observational standpoint, these complex sequences in volcanic and tectonic regions share many similarities: seismicity rate fluctuations, earthquakes migration, and activation of large seismogenic volume despite the usual small seismic moment released. The underlying mechanisms are local increases of the pore-pressure, loading/stressing rate due to aseismic processes (creeping, slow slip events), magma-induced stress changes, earthquake-earthquake interaction via static stress transfer or a combination of those. Yet, the physics behind such transients, seismo-genesis and the ultimate reasons for the occurrence of swarm-like rather than mainshock-aftershocks sequences, is still far beyond a full understanding.

This session aims at putting together studies of swarms and complex seismic sequences driven by aseismic transients in order to enhance our insights on both the physics of such transients and the earthquake source properties. Contributions focusing on the characterization of these sequences in terms of spatial and temporal evolution, source and scaling properties, and insight on the triggering physical processes are welcome. Multidisciplinary studies using observation complementary to seismological data, such as fluid geochemistry, deformation, and geology are also welcome, as well as laboratory and numerical modeling simulating the mechanical condition yielding to swarm-like and complex seismic sequences.

The links between crustal tectonics, mantle dynamics and climate-controlled surface processes, such as erosion, sediment transport and deposition together with sea-level variations, have been long recognized as primary drivers of the evolution of mountain belts and sedimentary basins.

The quantification of surface uplift-subsidence, erosion-sedimentation, thermal evolution and magmatism in the mantle and crust is a prime challenge in Earth Sciences. Since these processes and their feedback mechanisms act on a wide range of spatial and temporal scales, understanding orogenic and basin dynamics requires field data, geophysical and well data, geodetic measurements, geo-thermochronological studies as well as numerical and analogue modelling studies.

With this session we aim to bring together scientists from different fields that use emerging observation and frontier modelling techniques to improve our understanding of the links between orogenic or sedimentary basin evolution and their connection to surface, crustal, mantle and climatic forcing.
The rationale of the session is also to challenge geoscientists to apply their knowledge of deep and surface processes towards the new economic frontiers in Earth Science, such as the exploitation of geothermal energy and climate change mitigation through CO2 and H storage.
We encourage studies applying multi-disciplinary and innovative methods from worldwide natural laboratories.

The interplay of deep Earth processes with evolving atmospheric and hydrospheric conditions has shaped our planetary surface over billions of years. These solid Earth processes have modulated planetary habitability and biological evolution, driving biogeographic dispersal of species, as well as influencing oceanic and atmospheric circulation, climate, sea level, and even the emplacement of key economic mineral deposits. Recent decades have largely seen a focus on paleogeographic models incorporating plate tectonic reconstructions and mantle convection models. However, in recent years the improvement in computational resources and development of Earth system tools have cleared the way towards exciting deep-time Earth models with increasing complexity (such as biosphere feedbacks and carbon cycling) and spatio-temporal resolution. In addition, more attention has been given to sedimentological, paleobiological, and other geological and proxy data to constrain models of paleogeography, paleo-climate and surface processes.

We invite submissions from areas of tectonics, geodynamics, paleogeography, sedimentology, paleoclimatology, and all fields related to constraining Earth’s ancient geographies and the processes that shape them. We welcome submissions that are analytical or lab-focused, field-based, or involve numerical modelling of one or more Earth system components at regional or global scales. The session will also celebrate the contributions of early career researchers, open/community philosophy of research, and innovations that have adopted inter-disciplinary approaches.

Topography is the result of the competition between processes acting at different spatial and temporal scales. Tectonics, climate, and surface processes all leave fingerprints on modern topography, making it difficult for researchers to univocally characterize their contribution to shaping landscapes. Morpho-structural and geomorphic features provide the possibility to quantify the nature and the magnitude of the interaction between tectonics, climate, surface processing, and evolving topography from shorter to longer term timescales.
For instance, hillslope features, bedrock streams, topographic gradients and fluvial dynamics develop into the evolving landscape from the coastal to the high-relief areas. The use of laboratory, numerical and mathematical modelling and the recent advances in geochronological and thermochronological techniques, allow quantitative constraints on the magnitude, rates, and timing of topographic changes.
Moreover, a correct quantification of the interaction between surface processes and endogenous dynamics plays a major role in the evaluation also of geological hazards and related risks. Since the last decades, several techniques have been developed to assess the landscape evolution processes, dealing with analogue numerical models, geodetic tools (GPS and satellite images analysis) and quantifying techniques (cosmogenic nuclides and thermochronometric data). Overall, this data could be crucial when interpreting data coming from field observations.
We invite contributions aiming to link analogue, numerical models, with quantitative techniques, in supporting field interpretations.

It is now well known that the coupling between tectonics, climate and surface processes governs the dynamics of mountain belts and basins. However, the amplitude of these couplings and their exact impact on mountain building are less understood. First order quantitative constraints on this coupling are therefore needed. They can be provided by geomorphic and sedimentary records including longitudinal river profiles, fluvial and marine terraces, landslides, downstream fining trends, growth strata, sediment provenance, sequence stratigraphy, and changing depositional environments. In addition, such interaction may be explored also by geodetic analyses (e.g., GPS, UAV and satellite images analyses) as well as with innovative geo-informatic approaches. Moreover, the increasing integration of geochronological methods for quantifying erosion rates and source-to-sink sediment transfer with landscape evolution, stratigraphic, climatic, and tectonic models allows us to advance our understanding of the interactions between surface processes, climate and tectonic deformation.

We invite contributions that use geomorphic, geochronologic and/or sedimentary records to understand tectonic deformation, climate histories, and surface processes, and welcome studies that address their interactions and couplings at a range of spatial and temporal scales. In particular, we encourage coupled catchment-basin studies that take advantage of numerical/physical modelling, geochemical tools for quantifying rates of surface processes (cosmogenic nuclides, low-temperature thermochronology, luminescence dating) and high resolution digital topographic and subsurface data. We invite contributions that address the role of surface processes in modulating rates of deformation and tectonic style, or of tectonics modulating the response of landscapes to climate change.

Continental rifting is a complex process spanning from the inception of extension to continental rupture or the formation of a failed rift. This session aims at combining new data, concepts and techniques elucidating the structure and dynamics of rifts and rifted margins. We invite submissions highlighting the time-dependent evolution of processes such as: initiation and growth of faults and ductile shear zones, tectonic and sedimentary history, magma migration, storage and volcanism, lithospheric necking and rift strength loss, influence of the pre-rift lithospheric structure, rift kinematics and plate motion, mantle flow and dynamic topography, as well as break-up and the transition to sea-floor spreading. We encourage contributions using multi-disciplinary and innovative methods from field geology, geochronology, geochemistry, petrology, seismology, geodesy, marine geophysics, plate reconstruction, or numerical or analogue modelling. Special emphasis will be given to presentations that provide an integrated picture by combining results from active rifts, passive margins, failed rift arms or by bridging the temporal and spatial scales associated with rifting.

It is becoming increasingly apparent that continental rifting, breakup, and ocean spreading involve complexities not easily explained by standard models, especially in oblique and transform settings. The unexpected discovery of continental material far offshore, e.g. at the Rio Grande Rise, and realisation of the importance of obliquity and time-dependence in rifting, challenge conventional tectonic models. This session aims to bring together new observations, models, and ideas to help us understand the complex factors influencing continental rifting, breakup and ocean spreading, including oblique and transform settings. Works investigating time-dependant controls on rifting mechanisms, plate kinematics, strain localisation, obliquity, plate interior deformation, inherited lithospheric structures, interaction and feedbacks of rift processes, lithospheric and mantle derived driving forces, magmatism, syn-rift sedimentation, and other controls on rifting, are therefore welcomed to this session. Contributions from any geoscience discipline, including marine geophysics, seismology, ocean drilling, geochemistry, petrology, plate kinematics, tectonics, structural geology, numerical and analogue modelling, sedimentology and geochronology etc., are sought. We particularly encourage cross-disciplinarity, the spanning of spatio-temporal scales, and thought-provoking studies that challenge conventions from any and all researchers.

Movements across faults allow part of Earth’s surface to move in response to forces driven by tectonic plate motions. Mid-oceanic ridges (MORs) provide the unique opportunity to study two of the three known plate motions: divergence (at the ridge axis) and strike-slip motion along transform faults (crosscutting the ridge axis). Knowledge on active and past processes building and altering the oceanic lithosphere has increased over the past 20 years due to improvements in deep sea technologies and numerical modeling techniques. Yet, several questions remain open, such as the relative role of magmatic, tectonic and hydrothermal processes in the building of the oceanic lithosphere at the ridge axis, especially at slow and ultra-slow spreading ridges and at their intersection with transform faults. Transform faults and their older parts, i.e., the fracture zones, are still poorly studied features. For a long time, they were considered as cold and, for fracture zones, inactive; however, evidences of magmatism have been observed inside both features. Given the complex network of faults existing within these structures, they represent ideal pathways for hydrothermal percolation into the Earth’s lithosphere and may therefore play a significant role in the chemical and the thermal budget of the planet, as well as in the fertilization processes of the oceans in nutrients. This session objective is to share recent knowledge acquired along mid-oceanic ridge axes, transform faults and fracture zones. Works using modern deep-sea high-resolution techniques are especially welcome. The session also welcomes recent developments in thermo-mechanical models, which integrate geophysical and geological data with numerical modeling tools, bridging the gap between observations and numerical models.

Fold-and-thrust belts and accretionary prisms are key geological features occurring all around the globe. They mostly develop along convergent plate boundaries although they may also form along passive margins or other super-critical slopes by a gravitationally driven stress field. Fold-and-thrust belts can display a varied range of scales, may involve the whole continental lithosphere or just the uppermost sedimentary cover and can differ in their spatial extent, longevity of their formation and the rock types involved. Their geometry and kinematic evolution strongly depend on an ample variety of parameters (rheology, temperature, surface processes, structural inheritance, mechanical stratigraphy…), the understanding of their effects being fundamental for the comparison of different fold-and-thrust belts and the development of common predictive models.
Fold-and-thrust belts have been intensely investigated, aiming to decipher their short- and long-term evolution. However, there are important questions that remain not fully understood: i) What is the effect of structural inheritance, décollements, syn-tectonic sedimentation and the interplay between them on mountain building processes? ii) How are transient and long-term rheological/mechanical characteristics and processes affecting the evolution of fold-and-thrust belts? iii) How can we better define deep orogenic geometries and better reconstruct the burial, thermal and kinematic evolution of orogens?
The here proposed session tackles these questions by considering a multidisciplinary approach. We look forward to receiving abstracts focusing on the short- and long-term dynamics and the geometry and structural evolution of fold-and-thrust belts by means of different methodological approaches, including (but not limited to) field structural geology, cross-section construction and balancing, 3D structural modelling, seismics and seismology, analogue and numerical modelling, rock mechanics, geomorphology, thermochronology and geophysics.

The Caledonian mountain belt represents a world-class example of a deeply denudated Himalayan-style orogen. The exposed crustal sections allow the study of all stages of the Wilson cycle and may contribute to our understanding of many fundamental processes in Earth Sciences, including (1) continental-rifting, break-up and ocean formation, (2) subduction plus arc-continent and continental collisions, (3) marginal basin formation, (4) deep crustal architecture of orogens, (5) (U)HP metamorphism, (6) orogenic wedge formation and dynamics, (7) the formation and evolution of crustal-scale shear zones, (8) fluid-rock interactions, (9) ductile and brittle deformation mechanisms, and (10) the dynamics of late- to post-orogenic extension and deep crustal exhumation.

This session aims to bring together scientists studying rocks and geological processes from all stages of the Caledonian Wilson cycle, i.e. from rifting to collision and post-orogenic extension, and welcomes sedimentological, petrological, geochemical, geochronological, geophysical, structural, and modelling contributions that help to improve our understanding of the Caledonides and mountain belts in general. Contributions related to the ICDP drilling project Collisional Orogeny in the Scandinavian Caledonides (COSC) are especially welcome.

Subduction drives plate tectonics, generating the major proportion of subaerial volcanism, releasing >90% seismic moment magnitude, forming continents, and recycling lithosphere. Numerical and laboratory modeling studies have successfully built our understanding of many aspects of the geodynamics of subduction zones. Detailed geochemical studies, investigating compositional variation within and between volcanic arcs, provide further insights into systematic chemical processes at the slab surface and within the mantle wedge, providing constraints on thermal structures and material transport within subduction zones. However, with different technical and methodological approaches, model set-ups, inputs, and material properties, and in some cases conflicting conclusions between chemical and physical models, a consistent picture of the controlling parameters of subduction-zone processes has so far not emerged.

This session aims to follow subducting lithosphere on its journey from the surface down into the Earth's mantle and to understand the driving processes for deformation and magmatism in the over-riding plate. We aim to address topics such as: subduction initiation and dynamics; changes in mineral breakdown processes at the slab surface; the formation and migration of fluids and melts at the slab surface; primary melt generation in the wedge; subduction-related magmatism; controls on the position and width of the volcanic arc; subduction-induced seismicity; mantle wedge processes; the fate of subducted crust, sediments and volatiles; the importance of subducting seamounts, LIPs, and ridges; links between near-surface processes and slab dynamics and with regional tectonic evolution; slab delamination and break-off; the effect of subduction on mantle flow; and imaging subduction zone processes.

With this session, we aim to form an integrated picture of the subduction process, and invite contributions from a wide range of disciplines, such as geodynamics, modeling, geochemistry, petrology, volcanology, and seismology, to discuss subduction zone dynamics at all scales from the surface to the lower mantle, or in applications to natural laboratories.

Convergent plate boundaries can result in a wide variety of tectonic feature from collisional orogens (e.g. the Himalaya or Pyrenees) through subduction orogens (e.g. the Andes or Taiwan) to arc-back-arc systems (e.g. Sea of Japan or the Aegean). These tectonic settings might transition from one to another like in Southeast Asia, where there is geodynamic inversion of the east dipping Manila oceanic subduction South of Taiwan, that evolves northward, first, into a Continental Subduction (collision) onshore Taiwan, then secondly, east of Taiwan, into the north dipping Ryukyu arc/continent subduction.

Recently a large volume of high quality and high resolution geophysical and geological data had been acquired that could help us better understand the processes that govern subduction, collision and back-arc extension. Our session has a special focus on overriding plate deformation as it shows a great variety between different systems from extension dominated settings to compression dominated ones.

In this session authors are encouraged to share their work on the tectonic or magmatic features convergent plate boundary settings, as well as on the study of the processes contributing to the formation, evolution, and shaping of such systems. The conveners encourage contributions using multi-disciplinary and innovative methods from disciplines such as, but not restricted to, field geology, thermochronology, geochemistry, petrology, seismology, geophysics and marine geophysics, and analogue/numerical modelling.

Ophiolites, mélanges, and blueschists (OMB) are significant components of both accretionary and collisional orogenic belts and provide critical quantitative constraints for the timing of rift-drift, seafloor spreading and subduction initiation, ophiolite emplacement and collision events, peak P–T conditions during orogeny, and exhumation within subduction channels and along suture zones. Typical accretionary orogenic belt examples are exposed around the circum-Pacific region and in the Central Asian Orogenic Belt, whereas characteristic collisional orogenic belts occur in the circum-Mediterranean region, Alpine–Himalayan–Tibetan belt, Uralides, Taiwan and Papuan belts, Tasmanides, and Appalachians. Ophiolites and mélanges in these two major types of orogenic belts may show major differences in their crustal anatomies and geochemical fingerprints.

Collectively, OMB complexes and ocean plate stratigraphy (OPS) assemblages display the archives of ocean basin development, subduction initiation, crustal growth via accretionary processes (i.e., offscraping–shallow underplating) and volcanic arc formation at convergent margins, deep tectonic underplating and exhumation within subduction channels, and thermal evolution of subducting slabs. Therefore, systematic documentation of the tectonomagmatic settings of ophiolite formation, mechanisms and processes of mélange development (including non-metamorphosed ones), and P-T-t paths of both blueschist assemblages and high–temperature metamorphic belts in orogenic belts provide significant constraints for a quantitative establishment of the Wilson Cycle evolution of ancient ocean basins and the geodynamics of accretionary and collisional orogenic belt development.

This session will provide an international forum for interdisciplinary presentations and discussions on the diverse origins of OMB terrains and OPS assemblages, and their significance in probing the crustal anatomy and geodynamic evolution of accretionary and collisional belts around the world in a multi-scale approach. We welcome contributions dealing with the structural geology–tectonics, geochemistry–petrology, geochronology, and geophysics–geodynamics of OMB and OPS terrains, as well as numerical and analogue modelling of divergent and convergent margin processes that involve OMB evolution.

We invite contributions based on geological, tectonic, geophysical and geodynamic studies of the Tethyan Belt, Central Asia, and the Circum Pacific margins. We particularly invite interdisciplinary studies, which integrate observations and interpretations based on a variety of methods. This session will include a suite of studies of these regions with the aim of providing a comprehensive overview of their formation and evolution, influence of the tectonic features on climate, biodiversity, human habitat, and topographic change.
The Tethyan Belt is the most prominent collisional zone on Earth, covering the vast area between far eastern Asia and Europe. The geological-tectonic evolution of the belt has led to significant along-strike heterogeneity in its various regions, including the SE-Asian subduction-collision system, the Tibetan-Himalayan region, the Iranian Plateau, Anatolia, and the Alpine orogen. The Tethyan Belt is the result of subduction of the Tethyan Oceans, including significant terrane amalgamation, and collisional tectonics along the whole belt. The belt is today strongly affected by the ongoing collision of Eurasia with the African, Arabian and Indian plates and the large-scale geometry of the Cenozoic mountain ranges is often determined by inherited features. The long formation history and the variability of tectonic characteristics and deep structure of the region make it a natural laboratory for understanding the accretion processes that have shaped the Earth through its history and have led to the formation of vast resources in the crust.
The circum-Pacific domain has been undergoing multiple re-orientations in subduction and given rise to basin-mountain systems in both the eastern and western Pacific continental margins since the late Mesozoic. We welcome contributions on (1) the formation/origin and evolution of lithosphere architecture, (2) spatial-temporal evolution of Earth’s surface topography, (3) evolution of basin-mountain systems, and (4) 4-D geodynamic models of eastern and western Pacific continental margins.

We invite contributions that address the present and past structure and dynamics of the Alpine orogens and the back-arc basins of the Mediterranean area, which in the last decades has been the target of broadband large-scale passive experiments. The TopoIberia-Iberarray project, carried out in the 2000s in the Iberian Peninsula, is a successful example of the scientific progress that these experiments allow. More recently, the international AlpArray mission and related projects have generated a large amount of new data, not only seismic, to test the hypothesis that mantle circulation driving plates’ re-organization during collision has both immediate and long-lasting effects on the structure, motion, earthquake distribution and landscape evolution in mountain belts. Links between Earth’s surface and mantle have been forged by integrating 3D geophysical imaging of the entire crust-mantle system, with geologic observations and modelling to provide a look both backwards and forwards in time, the 4th dimension. This integrated 4D approach, initially focused on the Alps, has been expanded to the Pannonian-Carpathian region, with the ongoing PACASE experiment. A new initiative, AdriaArray, based on the deployment of the extensive AdriaArray Seismic Network, is underway to cover the Adria plate on both sides, including the Apennines and Dinarides-Hellenides, to shed light on plate-scale deformation and orogenic processes in this dynamic part of the Alpine-Mediterranean chain. This session provides an interdisciplinary platform for highlighting the newest results and open questions of the aforementioned projects, regions and themes.

In the last decades, the paleogeography, tectonic and kinematic evolution of Western Mediterranean region have been largely debated. One of the main difficulties in proposing consensual reconstructions is the complex patchwork of polysized blocks involved in the Variscan orogeny. The main blocks that experienced differential evolution during the Alpine cycle are Iberia, Adria and the Corsica-Sardinia/AlKaPeCa domains. The Cenozoic geodynamics of the Western Mediterranean and the diffuse Eurasia-Africa boundary hamper easy reconstructions. Evidence of the complex evolution, related to two superposed orogeneses, is recorded by several basins distributed along the Mediterranean area. The Variscan tectono-metamorphic phenomena are recorded in the Paleozoic successions exposed in the Betic-Rifian Arc, Algeria, Calabria-Peloritani Arc, Apennines, Corsica-Sardinia block, and the Alps. The Alpine tectono-metamorphic evolution, superposed on part of these ancient basements, is widespread in the Mesozoic to Cenozoic stratigraphic record preserved in the Mediterranean Alpine Chain with spectacular syn- to late-orogenic compressional and extensional deformation.
Several Permian to Mesozoic rift systems, conditioned by crustal-scale shear zones, developed in late/post-Variscan times. The polyphase evolution of these basins is related to the early breakup of Pangea and the opening of both the southern North Atlantic and the Bay of Biscay. These basins were subsequently inverted or involved in the Alpine orogens to accommodate the Africa-Eurasia convergence during Late Cretaceous to Tertiary times. The interplay between tectonics and sedimentation ruled the synorogenic sedimentation in the Foreland Basin System. Sedimentary facies analysis and paleoenvironment evolution of depositional systems, together with sediment provenance and paleogeographic/paleoecologic/paleoclimatic reconstructions, provide further constraints to trace the evolution of sedimentary basins. We welcome contributions dealing with prominent geological structures, mountain belts, and sedimentary basins which recorded the past configuration of the Iberia-Eurasia-Adria-Africa plate boundary(s). We encourage submission of studies presenting new insights including geology (tectonics, paleontology, stratigraphy, sedimentology, petrology, geochronology, thermochronology, and geochemistry), geophysics (paleomagnetism, seismicity, seismic imaging/anisotropy, gravity), modelling (numerical and analogue).