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The Kristallbrocken are a characteristic centimetre-to decimetre-sized, laminated halite fabric type occurring in the Stassfurt Formation in the Zechstein Basin.

The bromide profile of the bedded Zechstein 2 rock salts in the Southern Permian Basin is characterized by a continuous increase in the bromide contents from base to top, indicating progressive evaporation of sea water. Former studies have suggested that the bromide distribution in domal salts is more irregular, raising such questions as whether there is a causal relationship between bromide distribution and deformation‐related processes or whether various halite types with different primary bromide contents account for such irregularities. In this study, the bromide distribution of a defined stratigraphic section (Hauptsalz) of the Zechstein 2 was investigated in three salt deposits, with bedded salt (Teutschenthal) compared with domal salts (Morsleben and Gorleben). Furthermore, two different halite types (Kristallbrocken, matrix) were distinguished during sampling. Comparison between the locations reveals that: (i) the characteristic trend of the bromide profile was generally preserved in both the bedded and the more intensely deformed domal salts; (ii) the dispersion of bromide contents along the running average curve is lower in domal salt, especially in the lower half of the Hauptsalz; and (iii) the Kristallbrocken are absent in the lower half of the Hauptsalz of Morsleben and Gorleben. The absence of the Kristallbrocken and the lower dispersion of the bromide contents in the domal salts are clear indications for the influence of salt migration‐related processes on the bromide distribution characteristics. It shows that these processes are associated with a redistribution of bromide, which eventually results in a homogenization of the originally varying bromide contents. On the other hand, preservation of the characteristic trend in the bromide profiles indicates that large‐scale brecciation, folding processes or circulating bromide‐rich fluids played only a minor role during the formation of the salt domes. Selective sampling of the Kristallbrocken and matrix halite displays a disparity in bromide content that is not consistent between the studied locations. These specific phenomena might be related to different depositional locations in the Zechstein Basin or to post‐depositional processes.

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This dissertation includes four studies that were concerned with geochemical characteristics and deformation mechanisms of rock salt. The studies focused especially on the rock salt of the Stassfurt Formation (Zechstein 2) and samples were taken from different salt deposits of Germany and the Netherlands.The first study investigated the relationship between deformation intensity and bromide characteristics of the rock salt. For this, the bromide distribution of a defined stratigraphic section (Hauptsalz) of the Stassfurt Formation (Zechstein 2) was investigated in three salt deposits, with bedded salt (Teutschenthal) compared to domal salts (Morsleben, Gorleben).The comparison between the locations yielded the following findings: (1) The characteristic trend of the bromide profile can be observed in both the bedded and the more intensely deformed domal salts. (2) The dispersion of bromide contents along the running average curve is lower in Morsleben and Gorleben than in Teutschenthal, especially in the lower half of the Hauptsalz. (3) The Kristallbrocken are absent in the lower half of the Hauptsalz of Morsleben and Gorleben. On the one hand, the lower dispersion of the bromide contents in the domal salts and the absence of the Kristallbrocken are clear indications for the influence of salt migration-related processes on the bromide distribution characteristics. It shows that these processes are associated with a redistribution of bromide, which eventually results in a homogenisation of the originally varying bromide contents. On the other hand, preservation of the characteristic trend in all bromide profiles indicates that large-scale brecciation, folding processes, or circulating bromide-rich fluids could play only a minor role during the formation of the salt domes.The topic of the second and third study of this work was the laminated halite type Kristallbrocken that is characteristic for the Stassfurt Formation (Z2) rock salt. The investigations of both studies contributed to the understanding of the structure, the formation and the deformation mechanisms of this halite type. X-ray texture analyses on 4 Kristallbrocken samples from the salt deposit Teutschenthal demonstrated that the Kristallbrocken are single crystals and that they can be regarded as relics of formerly larger "single crystal-layers". Microscopic investigations showed that the internal lamination of the Kristallbrocken consists of several types of sulfate inclusions (anhydrite, polyhalite).Especially characteristic are anhydrite aggregates with surrounding brine. The original size of the monocrystalline beds, their high amount of relatively large solid inclusions as well as the characteristic sedimentary features make it unlikely that these laminated single crystals were grown directly from a solution. A more probable scenario is that an originally fine-grained,