External and internal salt geometries – a mining and geoscience review

The Central European Basin System contains the Permian Zechstein salt giant, which includes a large number and variety of subsurface salt structures formed by salt tectonics in Mesozoic and Cenozoic times. Early descriptions of salt-body geometries originate mostly from salt-mining activities of the early 20th century in Germany and Poland. Inventories found in the mines are primarily documented as line drawings and from descriptions of miners and mine geologists. With the advancement of geophysical acquisition of the past decades, in particular active multidimensional seismic-reflection surveying combined with borehole geophysics and numerical and analogue modelling techniques, the description and interpretation of the external form of salt bodies and internal salt stratigraphy and geometry has made a major step forward. This study highlights the value of integrating detailed high-resolution salt-system knowledge from legacy field and mining data with modern 2D and 3D seismic-reflection data and observations from modelling for improved geological subsurface interpretations in salt terrains. Such integration will play an important role in the increased utilization of subsurface salt structures in the context of energy-transition strategies and the sustainable storage of renewable energy materials and waste. • Subsurface salt will play a key role in renewable energy storage scenarios. • Future sustainable use of subsurface salt structures requires integrated studies. • Outcrops and subsurface mines provide valuable insights into salt bodies. • Historic and modern data and studies in salt need to be combined. • Integrated geoscience and engineering approach improves storage site characterization.