Modelling of geological subsurface utilisation in terms of chemical or thermal energy storage as well as hydrocarbon production and storage are required to ensure a safe and sustainable energy supply. However, utilisation of the geological subsurface may induce changes in the recent hydraulic, thermal, mechanical and chemical regimes. Our session aims at the integration of experimental and numerical modelling methods for quantification and prediction of the potential impacts resulting from geological subsurface utilisation including:
• Site characterisation and determination of site-specific geological and process data.
• Development of static geological models.
• Integration of experimental data into static and dynamic models as well as application of numerical models for experimental design and interpretation.
• Development and benchmarking of modelling tools.
• Model and parameter upscaling techniques.
• Model coupling addressing the interaction of thermal, multi-phase flow, geochemical and geomechanical processes in the fluid-rock system.
• Application of modelling tools for site characterisation and prediction of potential impacts.
• Methods for risk assessment and efficient site operation.

Public information:
Session will take place following the EGU2020 schedule via zoom (meeting link: https://us02web.zoom.us/j/89217824952) at Thursday, May 7, 10:45 am CEST.

Numerous cases of induced/triggered seismicity have been reported in the last decades, directly or indirectly related to anthropogenic activity for the geo-resources exploration. Induced earthquakes felt by local population can often negatively affect public perception of geo-energies and may lead to the cancellation of important projects. Furthermore, large earthquakes may jeopardize wellbore stability and damage surface infrastructure. Thus, monitoring and modeling processes leading to fault reactivation, (seismic or aseismic) are critical to develop effective and reliable forecasting methodologies during deep underground exploitation. The complex interaction between injected fluids, subsurface geology, stress interactions, and resulting induced seismicity requires an interdisciplinary approach that accounts for coupled thermo-hydro-mechanical-chemical processes to understand the triggering mechanisms.
In this session, we invite contributions from research aimed at investigating the interaction of the above processes during exploitation of underground resources, including hydrocarbon extraction, wastewater disposal, geothermal-energy exploitation, hydraulic fracturing, gas storage and production, mining, and reservoir impoundment for hydro-energy. We particularly encourage novel contributions based on laboratory and underground near-fault experiments, numerical modeling, the spatio-temporal relationship between seismic properties, injection/extraction parameters, and/or geology, and fieldwork. Contributions covering both theoretical and experimental aspects of induced and triggered seismicity at multiple spatial and temporal scales are welcome.

Fractures are discontinuities in rocks that are present in almost all geological settings and at any scale. They may represent small-scale fissures or build up large scale faults. Fractures are extreme forms of heterogeneities, often with a small extension but huge impact.
The presence of fractures modifies the bulk physical properties of the original media by many orders of magnitudes, and they often introduce a strongly nonlinear behavior. This refers in particular to the mechanical properties via reduction of strength and stiffness. Fractures also provide the main flow and transport pathways in hard rock aquifers, dominating over the permeability of the rock matrix, as well as creating anisotropic flow fields and transport. Understanding their hydraulic and mechanical properties of fractures and fracture networks thus are crucial for predicting the movement of any fluid such as of water, air, hydrocarbons, or CO2. Consequently, fractures are of great importance in various disciplines such as hydrogeology, hydrocarbon reservoir management, and geothermal reservoir engineering.
The geologist toolbox to explore and model fractured rocks is getting more and more extended. This session is dedicated to novel ideas and concepts on treating the challenges related to the generic understanding, the characterization and the modelling of fractured geological media.
Contributions are welcome from the following topics
• Exploration methods for mechanical and/or hydraulic characterization of fractured media
• Structural construction of fractured media by deterministic or stochastic approaches,
• Representation of static hydraulic and/or mechanical characteristics of fractured media involving continuous or discontinuous methods,
• Simulation of dynamic processes and the hydraulic and/or mechanical behavior of fractured media,
• Theoretical studies and field applications in fractured geological formations,
• Concepts of accounting for fractured properties specifically in groundwater, petroleum or geothermal management applications.

Dissolution, precipitation and chemical reactions between infiltrating fluid and rock matrix alter the composition and structure of the rock, either creating or destroying flow paths. Strong, nonlinear couplings between the chemical reactions at mineral surfaces and fluid motion in the pores often leads to the formation of intricate patterns: networks of caves and sinkholes in karst area, wormholes induced by the acidization of petroleum wells, porous channels created during the ascent of magma through peridotite rocks. Dissolution and precipitation processes are also relevant in many industrial applications: dissolution of carbonate rocks by CO2-saturated water can reduce the efficiency of CO2 sequestration, mineral scaling reduces the effectiveness of heat extraction from thermal reservoirs, acid rain degrades carbonate-stone monuments and building materials.

With the advent of modern experimental techniques, these processes can now be studied at the microscale, with a direct visualization of the evolving pore geometry. On the other hand, the increase of computational power and algorithmic improvements now make it possible to simulate laboratory-scale flows while still resolving the flow and transport processes at the pore-scale.

We invite contributions that seek a deeper understanding of reactive flow processes through interdisciplinary work combining experiments or field observations with theoretical or computational modeling. We seek submissions covering a wide range of spatial and temporal scales: from table-top experiments and pore-scale numerical models to the hydrological and geomorphological modelling at the field scale. We also invite contributions from related fields, including the processes involving coupling of the flow with phase transitions (evaporation, sublimation, melting and solidification).

Public information:
There will be a zoom session connected with the session on Tue, May 5th, at 18.00 CET

https://us04web.zoom.us/j/79628870111

Society today demands sustainable technical solutions that reconcile the needs of society with those of nature . These solutions must coordinate between different and often competing demands within a sub-system (irrigation, ecological flow, power generation) and the variety of different uses of environmental resources across systems (e.g., power from water, wind, sun, or waves). The short term variability of precipitation, wind speed, sunshine, and other for environmental resources create a need for complex decisions to be taken in real time. Advances in real-time automatic control will play an essential role in making this possible. Moreover, while one might debate whether or not stationarity is dead, it is clear that fully deterministic models cannot cope with the connected world of today. The complex interactions of the randomness in the availability and quality of different resources calls out for an at least partially stochastic modelling approach.
We particularly invite contributions on:
• Stochastic modelling and control;
• Real-time control of environmental systems;
• Real-time monitoring and control of water quality;
• Real-time control of rural water systems;
• Real-time control of urban water systems.

The session is associated with Panta Rhei working group ``Natural and man-made control systems in water resources''.

Recent advances in deformation sensing have led to new applications in various geophysical disciplines such as earthquake physics, broadband seismology, volcanology, seismic exploration, strong ground motion, earthquake engineering and geodesy.
New developments in translation, rotation and strain sensing enable the complete observation of seismic ground motion and deformation. Applications are manifold, ranging from the reduction of nonuniqueness in seismic inverse problems to the characterization, separation and reconstruction of the seismic wavefield.
Among others, fibre optic technologies is bound to become a standard tool for crustal exploration and seismic monitoring thanks to: (i) easier installation (low cost, simpler installation and maintenance, robustness in harsh environment); (ii) high spatial and temporal resolution over long distance; (iii) broader frequency band. There have been significant breakthroughs, applying fibre optic technologies to interrogate cables at very high precision over very large distances both on land and at sea, in boreholes and at the surface.
These developments overlap with considerable improvements in optical and atom interferometry for inertial rotation and gravity sensing which has led to a variety of improved sensor concepts over the last two decades.
We welcome contributions on theoretical advances and applications of novel sensing methodologies in seismology, geodesy, geophysics, natural hazards, oceanography, urban environment, geothermal investigations, etc. including laboratory studies, large-scale field tests and modelling.

We are happy to announce Nathaniel J. Lindsey as invited speaker.

Hydraulic, thermal, chemical and mechanical processes (coupled or uncoupled) in saturated media are of increasing interest in many hydrogeological contexts and their understanding is a major challenge in modern hydrogeology. These processes play a major role in natural systems, such as in thawing rock and soil and volcanic environments, but also in anthropogenic systems where human activities are intensifying the pressure on groundwater and subsurface space use. The understanding of these processes is of paramount importance to:
• Ascertain the role of groundwater in the context of geothermal energy and mitigating its impacts. It is also needed to consider the seasonal and long-term development of thermal and mechanical conditions in aquifers, heat transfer across aquifer boundaries and between fluid and rock are focus points, and the influence of precipitated fluid compounds.
• Enhance the development of underground constructions improving its efficiency and minimizing impacts.
• Achieve an accurate characterization of subsurface flow, transport and heat transfer, which require observations of induced or natural variations of the thermal regime. There are many ongoing research projects studying heat as a natural or anthropogenic tracer, for characterizing aquifers, flow conditions, and crucial transport processes, such as mechanical dispersion.
• Determine the fate and evolution of pollutants and micropollutants introduced in natural systems by the leakage from sewers and the discharge of wastewaters.
• Explain the influence of urbanized areas and sealed surfaces in the aquifer behavior.
• Improve predictions concerning groundwater extraction, injection and/or both, and their associated impacts.
• Understand the consequences and risks associated with CO2 storage.
• Identify and quantify aspects that may impact the urban groundwater and investigate methods for minimizing their influence (e.g., artificial groundwater recharge, improvement of the “natural” recharge in urban areas, reuse of pumped groundwater, redesign of geothermal systems, etc.) and to enhance groundwater management strategies.
This session welcomes contributions that deliver new insight in the field of hydraulic, thermal, chemical and mechanical processes in saturated media, specially, but not restricted to, in urban aquifers, including experimental design, reports from new field observations, demonstration of sequential or coupled physical and numerical modelling concepts or case studies.

Geophysical methods have a great potential for characterizing subsurface properties and couple THM processes to inform geological, reservoir, hydrological, and (bio)geochemical studies. In these contexts, the classically used geophysical tools only provide indirect information about subsurface heterogeneities, reservoir rocks characteristics, thermo-hydro-mechanical coupling, and associated processes (e.g. flow, transport, bio-geochemical reactions). Rock physics relationships hence have to be developed to provide links between physical properties (e.g. electrical conductivity, seismic velocity or attenuation) and the intrinsic parameters of interest (e.g. fluid content, hydraulic properties, coupled processes). In addition, geophysical methods are increasingly deployed as time-lapse, or even continuous, and distributed monitoring tools on more and more complex environments. Here again, there is a great need for accurate and efficient physical relationships such that geophysical data can be correctly interpreted (e.g. included in fully coupled inversions). Establishing such models requires multidisciplinary approaches since involved theoretical frameworks differ. Each physical property has its intrinsic dependence to pore-scale interfacial, geometrical, and (bio)geochemical properties or to external condition (such as pressure or temperature). Each associated geophysical method has its specific investigation depth and spatial resolution which adds a significant level of complexity in combining and scaling theoretical developments with laboratory studies/validations and/or with field experiments. This session consequently invites contributions from various communities to share their models, their experiments, or their field tests and data in order to discuss about multidisciplinary ways to improve our knowledge on reservoir and near surface environment.