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Zusammenfassung:
In northwestern Europe, the upper Permian Zechstein evaporites are a highly efficient seal for Carboniferous gas trapped in clastic Rotliegend reservoirs. The Zechstein evaporite succession and postsalt sediments experienced complex deformation during several tectonic phases in the German and Dutch part of the Southern Permian Basin, including extension and compression or transpression. However, controlled by late Permian topography, the number and thickness of the individual evaporite cycles vary, mainly correlating with the basin, slope, and platform settings of the Zechstein Sea. The main trigger mechanisms for early salt movement comprise extension and rafting of Lower Triassic sediments, syn-depositional fault activity within the subsalt, subsequent differential loading of postsalt sediments, and intrasalt heterogeneities. This latter caused thin-skinned salt tectonics with passive diapirism, which seeded the number of the salt highs observed today. Later reactivation, cessation, or formation of new salt highs was triggered by the massive change from extensional to compressional tectonics that began in Cretaceous times. Regional fault patterns were reactivated or newly formed during these tectonic phases, and they are often marked by elongated salt walls. A large drop in tectonic stresses since the onset of the Cenozoic caused a rather tabular draping of thick clastics and marks the cessation of major salt movements across the greater part of the Dutch and German Zechstein Basin. Since then, most of the Zechstein salt has been considered to be at rest.
