Rock salt formations have long been recognized as a valuable resource - not only for salt mining but for construction of oil and gas storage caverns and for isolation of radioactive and other hazardous wastes. Current interest is fast expanding towards construction and re-use of solution-mined caverns for storage of renewable energy in the form of hydrogen, compressed air and other gases. Evaluating the long term performance and safety of such systems demands an understanding of the coupled mechanical behavior and transport properties of salt. This volume presents a collection of 60 research papers defining the state-of-the-art in the field. Topics range from fundamental work on deformation mechanisms and damage of rock salt to compaction of engineered salt backfill. The latest constitutive models are applied in computational studies addressing the evolution and integrity of storage caverns, repositories, salt mines and entire salt formations, while field studies document ground truth at multiple scales. The volume is structured into seven themes:

• Microphysical processes and creep models
• Laboratory testing
• Geological isolation systems and geotechnical barriers
• Analytical and numerical modelling
• Monitoring and site-specific studies
• Cavern and borehole abandonment and integrity
• Energy storage in salt caverns

The Mechanical Behavior of Salt X will appeal to graduate students, academics, engineers and professionals working in the fields of salt mechanics, salt mining and geological storage of energy and wastes, but also to researchers in rock physics in general.
About the Author:

J.H.P. de Bresser (Hans de Bresser) is head of the High Pressure-Temperature (HPT) Laboratory in the Geosciences Faculty at Utrecht University and professor in Teaching and Learning in Earth Sciences. He obtained his PhD in 1991 based on a thesis on intracrystalline deformation of calcite. After a few years within industry, he returned to Utrecht University in 1994, working in the experimental rock deformation group at the HPT Laboratory. Hans has worked on deformation behaviour and microstructures in limestone and marble, olivine rocks, rock salt, clay rock and ice, covering the whole range from plastic behaviour at high temperature to frictional behaviour at relatively low temperature. An important focus of his work concerns the role of dynamic recrystallisation in flow behaviour and microstructure development. In addition, Hans has worked on structures in natural rocks in the Ardennes, Pyrenees, Alps and the Betic Cordillera of south-eastern Spain. Hans has been director of education of the bachelor and master degree programmes in Utrecht (2007-2014), director of the Honours College of Geosciences (2012-2015), and vice-dean of education of the Faculty of Geosciences (2014-2021).

M.R. Drury (Martyn Drury) is Professor of Structural Geology and Electron Microscopy in the Geosciences Faculty at Utrecht University. Martyn uses advanced microscopy to study physical and chemical processes in Earth materials. He obtained a PhD (1984) at Imperial College, London and after research fellowships in London, Utrecht and at the Australian National University, Martyn moved back to Utrecht and was appointed as Professor in 2010. He is currently scientific director of EPOS-NL, the Dutch large-scale infrastructure for geo-resources research. Martyn has worked on deformation and recrystallization mechanisms in metals, minerals and ice. He has published over 140 peer-reviews papers including 11 papers on the application of crystal orientation mapping methods to characterize microstructures and crystallographic preferred orientations in rock salt.

P. A. Fokker (Peter Fokker) is senior reservoir geomechanics scientist in the team "Applied Geosciences" at TNO. He is also guest researcher at Utrecht University and visiting professor at the Politecnico di Torino in Italy (DIATI) in reservoir engineering. His research interests are related to the sustainable use of the subsurface in the field of reservoir engineering and reservoir geomechanics, with a key link to geology and remote sensing. More specifically, his interests focus on modelling: developing fast models for reservoir engineering and linking these to reservoir simulation for productivity prediction and well testing, and developing fast geomechanical models to predict subsidence, fault reactivation, induced seismicity, salt cavern stability, and fracturing. Example applications are found in geothermal applications, salt mining, and CCS. Peter authored and co-authored about 50 publications in peer-reviewed journals and an equal amount of non-peer-reviewed conference contributions. He is a member of the UNESCO Working Group on Land Subsidence and in that function Chair of the Scientific Committee of TISOLS, the Tenth international Symposium on Land Subsidence, scheduled for April 2023.

M. Gazzani (Matteo Gazzani) is an assistant professor in the group of Energy and Resources, which is part of the Copernicus Institute of Sustainable Development at Utrecht University, Faculty of Geosciences. Before joining the Copernicus Institute in 2017, Matteo worked as senior scientist and as postdoctoral fellow at ETH Zurich in the Institute of Process Engineering. He obtained his Ph.D. cum laude in Energy and Nuclear Sciences and Technologies at Politecnico di Milano, where he also did his bachelor and master studies in Energy Engineering. During his doctoral studies he was awarded a Rocca fellowship for spending a visiting research period at the Massachusetts Institute of Technology, USA. Matteo's research focuses on the interface between energy systems, chemical processes and new technologies, and spans from gas separation processes to H2 production and storage, to multi energy systems design and optimization. Overall, he aims at supporting the energy transition for a CO2 net-negative society. Matteo has published more than 70 peer-reviewed papers, including recent works on H2 production and storage in salt caverns.

S.J.T. Hangx (Suzanne Hangx) is an assistant professor at the High Pressure-Temperature (HPT) Laboratory in the Geosciences Faculty at Utrecht University. Her research focusses on the chemical and physical processes that control rock material behaviour in the subsurface, along with the direct relevance of this field to societal issues, such as geological storage of CO2 and geo-energy production. She has worked both in industry (Shell Global Solutions, 2009-2014) and academia. For her work on CO2 storage, Hangx received the 2012 European Geosciences Union Outstanding Young Scientist Division Award in the Energy, Resources and Environment Division. She leads multiple national- and industry-funded projects related to geo-energy production and storage, including hydrogen storage in salt caverns and radioactive waste storage in salt formations.

A.R. Niemeijer (André Niemeijer) is Associate Professor at the High Pressure-Temperature (HPT) Laboratory in the Geosciences Faculty at Utrecht University with expertise in earthquake and fault mechanics and the effects of fluids. André obtained his PhD at Utrecht University in 2006. He completed three post-doctoral fellowships at Penn State University (USA), Istituto Nazionale di Geofisica e Volcanologia (Rome, Italy) and Utrecht University before becoming a permanent staff member in Utrecht in 2013. He is a laureate of several individual research grants from the national research council (NWO) as well as of an ERC starting grant. André has worked on faulting related topics relevant to both natural and induced seismicity using experimental, observational and modeling techniques. He has published 88 peer-reviewed papers and a book contribution, including 6 papers on salt deformation in simulated faults. In 2012, he received the European Geosciences Union outstanding young scientist award in the Division of Tectonics and Structural Geology.

C.J. Spiers (Chris Spiers) is Emeritus Professor at the High Pressure-Temperature (HPT) Laboratory in the Geosciences Faculty at Utrecht University. He led the lab as Prof. of Earth Materials until 2020, specializing in experimental rock and fault mechanics and effects of fluids. Chris gained his PhD from Imperial College, London. Following a Miller Fellowship at UC Berkeley (1980-81), he moved to Utrecht, receiving his chair in 1992. Chris has worked on topics from creep of crustal and upper mantle rock materials to seismic fault friction and to deformation of reservoir rocks, caprocks, coal and shales. Chris has served as Dean and Education Director in Earth Sciences at Utrecht and played a leading role in university and national research programmes on geo-resources and geo-storage. He has published more than 200 peer-reviewed papers and book contributions, including some 50 papers on rock salt deformation and transport properties. In 2017, he received the European Geosciences Union Néel Medal for his contribution to Rock Physics.