Salt as a 3D element in structural modeling - Example from the Central European Basin System

Based on a well constrained 3D structural model of the Central European Basin System, 3D modeling has been carried out to understand the regional-scale regularities between movements of the Upper Permian (Zechstein) salt and the major post-Permian tectonic events. The 3D reconstruction of the paleo-thickness of Upper Permian salt at the end of the Permian period demonstrates that areas of thickened Upper Permian salt correlate with the present-day distribution of the largest salt structures within the Central European Basin System. This spatial correlation implies that the distribution of salt thickness at the end of deposition partially controlled the structural style of the basin during post-Permian phases of salt tectonics. Moreover, the results of 3D salt redistribution for post-Permian times indicate that the initiation of salt movements took place in the Triassic. The Triassic extensional events triggered several phases of salt movements within the coeval depocenters of the Central European Basin System, such as the Gluecicstadt Graben, the Horn Graben, the Norwegian-Danish Basin (the Fjerritslev Trough and the Himmerland Graben) and the Polish Basin. During the Late Jurassic-Early Cretaceous extensional/transtensional tectonic event, the strongest salt movement occurred within the Central Graben, the Lower Saxony Basin and the Pompeckj Block. The intensity of the Late Jurassic-Early Cretaceous phase of salt tectonics is essentially declining from the marginal areas of the Central European Basin System towards the Horn Graben, the Glueckstadt Graben and adjacent areas. The late Early Cretaceous-early Late Cretaceous is characterized by tectonic quiescence without strong salt movements over the entire study area. The next regional phase of salt movements was triggered by Late Cretaceous-Early Cenozoic inversion, involving almost the entire Central European Basin System in terms of renewed salt movements. Inversion-related thick-skinned salt tectonics is observed along the NW-SE-trending Elbe Fault System and the Teisseyre-Tornquist Zone where strongest compressional deformations were localized. On the contrary, a thin-skinned character of salt movements was prevailing within the largest part of the North German Basin. Post-inversion Cenozoic subsidence was also accompanied by salt activity, related either to diapiric rise due to regional shortening and/or to local roughly E-W directed extension. The Cenozoic phase of salt movements was especially prominent within the marginal troughs of the Glueckstadt Graben. (C) 2012 Elsevier B.V. All rights reserved.