RISE – the Role and Influence of Salt in the Evolution of fold and thrust belts

Abstract: The scope of this project (RISE – the Role and Influence of Salt in the structural Evolution of fold and thrust belts) is quantifying the deformation of rocksalt and its influence on the structural evolution of fold and thrust belts. To achieve our goals, we will focus on the Romanian Carpathians and Transylvanian Basin. First, we will create and analyse high-resolution 3D models of fold structures in world-class outcrops in salt mines, reproduce the evolution of these salt structures by means of scaled analogue modelling and collect samples for microstructural analysis. This is the first integrated study combining such techniques in Romania and one of the few worldwide. The results of the microstructural analysis will be compared with the different structural settings exposed in mines and in rock salt layers with different strains and different rheological contrasts, as determined from fold morphologies. This, coupled with scaled analogue modelling experiments, will provide crucial insights into the deformation history, mechanical properties, paleo-stress, recrystallization and will provide improved quantitative models of rheology and evolution of the different salt structures in Romania and worldwide.

Project results (executive summary): The project entitled “RISE – the Role and Influence of Salt in the structural Evolution of fold and thrust belts” focused on the impact of salt on the structural evolution of orogens and other compressional salt structures, with special attention to the Carpathian Mountains of Romania and the Transylvanian Basin. The aim was to integrate field geological mapping, microstructural analysis of salt, analogue modelling, and virtual 3D models to analyze salt structures, both externally (through natural outcrops) and within mines. The integration of all these methods makes this study innovative, both in Romania and globally.

The objectives outlined in this research project were: 1) characterization of microstructures, composition, fabric, and kinematics of deformed salt structures in the compressional domain, and 2) integration of results from microstructural analysis, analogue (physical) models, and 3D digital models of salt outcrops and mines in Romania. Both objectives were successfully achieved, and to accomplish them, data were acquired, and a total of 30 high-resolution 3D models of mines and salt outcrops, ten analogue models, and over 50 salt samples were obtained, analyzed, and interpreted.

The results, including the 3D models and structural analyses, were disseminated through scientific articles and presentations at international conferences, contributing to the understanding of salt structure evolution and its potential applications, such as hydrogen storage. The findings obtained made significant contributions to understanding salt-related tectonic processes and were presented in three scientific articles (including one that is currently in review) and at multiple prestigious international conferences.

The discoveries resulting from this project have led to the consolidation of a team and a new project idea that has been submitted to another competition, not only to continue this research but also to make significant and innovative contributions to understanding the rates of uplift and erosion of salt structures in a continental temperate climate.

List of publications:

• Tămaș, D.M., Dohan, D., Barabasch, J., Tămaș, A., Schleder, Z., Krezsek, C., Urai, J.L. 2024 , A Review of Salt Tectonics in Romania’s Transylvanian Basin and implications for Energy Transition. Geological Society London, Special Publications, 555, https://doi.org/10.1144/SP555-2024-9
• Schléder, Z., Lăpădat, I.A., Trandafir, G., Fernandez, O., Tămaș, D.M., Tămaș, A., Filipescu, S., Krézsek, C., Rădoiaș, M.A. and Vasiliu, M., 2023, Structural inheritance and style within the Getic Depression, South Carpathians, Romania. Marine and Petroleum Geology, 106068. https://doi.org/10.1016/j.marpetgeo.2022.106068
• Bercea, R.I., Balc, R., Tămaș, A., Filipescu, S., Tămaș, D.M., Guillong, M., Szekely, S.F., Lukacs, R. 2023. Insights into the palaeoenvironments, structure and stratigraphy of the lower Miocene of the Eastern Carpathians Bend Zone, Romania. Geological Quarterly, 67(2), 25-50. http://doi.org/10.7306/gq.1673

List of conference presentations:

• Tămaș, D.M., Tămaș, A., Sava, G. O., Avram, A., and Timar-Gabor, A. 2024, Timing and rates of salt movement in the Romanian Eastern Carpathians: insights from Radiocarbon and OSL dating, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5204. https://doi.org/10.5194/egusphere-egu24-5204
• Tocariu, I. S. M., Tamas, A., Tămaș, D. M., Dohan, D., Lapadat, A., Schleder, Z., and Krezsek, C.: Analogue Modelling to Support Seismic Interpretation in the Eastern Carpathian Bend Zone, Romania, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-771. https://doi.org/10.5194/egusphere-egu24-771
• Tămaș, D.M., Tămaș, A., Dohan, D., Tocariu, I. S. M., Schleder, Z., Krezsek, C., and Urai, J., 2023, Salt tectonics and its influence on the development of the Romanian Carpathians, EGU General Assembly 2023, Vienna, Austria, EGU23-5438. https://doi.org/10.5194/egusphere-egu23-5438
• Tămaș, D.M., Adamuszek, M., Tămaș, A., Barabasch, J., and Urai, J. L., 2023, The role and control of impurities in the deformation of salt (Ocnele Mari salt mine, Romania). Tectonics Studies Group Conference, Leeds, UK.
• Tămaș, D.M., Tămaș, A. 2022, Importance of salt in energy transition: can machine learning help us to better constrain the geometries of salt bodies? “Ion Popescu-Voitești” Annual Scientific Session, Cluj-Napoca, Romania.
• Tămaș, D.M., Tămaș, A., Schléder, Z. and Krézsek, C. 2022, Coupling machine learning and subsurface data to define the geometry of a salt diapir: Eastern Carpathian Bend Zone. Seismic Encounters I – Budapest, Sept. 2022.
• Copoț, B., Tămaș, D.M., Tămaș, A., Krézsek, C., Schleder, Z., Lapadat, A. and Filipescu S., 2022, Effects of multiple detachments in thin-skinned fold and thrust belts: insights from analogue modelling. EGU General Assembly 2022, Vienna, Austria. https://doi.org/10.5194/egusphere-egu22-11360
• Tămaș, D.M., Tămaș, A., Barabasch, J., Rowan, M.G., Schleder, Z., Krézsek, C. and Urai, J.L., 2022, Do diapirs ever lose their heads? Insights from the Romanian Eastern Carpathians. EGU General Assembly 2022, Vienna, Austria. https://doi.org/10.5194/egusphere-egu22-4498

Digital outcrop models of salt exposures in Romania:

Most outcrops created within this project can be explored using THIS LINK.

Below are examples of the digital outcrop models created within this project: