Tectonics, sedimentation and salt dynamics in transtensional and transpressional basins, south maritimes basin, Nova Scotia

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Ancient and modern mountain ranges result from the collision of continental crust fragments, so called terranes. The terrane boundaries form crustal structures and fault systems that can be still active as compressional thrust faults in late stages of mountain building or may be reactivated later as continental strike-slip fault zone with horizontal displacements of 10's to 100's km during the post-collision stage. In overlap zones of fault segments or along bends the opposed displacement of adjacent crustal blocks can generate subsidence in fault-bounded sedimentary basins on top of the mobile basement of the former mountain range. The close neighbourhood to high mountain ranges provides high sediment supply. The variety of basin styles and sediment sources controls the deposition of continental to shallow marine sedimentary rocks including mineral, coal and petroleum resources. The large Palaeozoic Maritimes Basin in Atlantic Canada is such a late-orogene basin superimposed on a mosaic of Appalachian terranes. It consists of numerous smaller depocentres and fault-bounded basins with a thick basin fill of more than 12 km thickness that were created by major strike-slip motion along Appalachian terrane boundaries. Additionally, thick marine evaporite sediments (e.g. rock salt) in the basal part of the basin fill were mobilized by the loading of the overlying sediments during the later stages of basin formation causing salt diapirs and salt-flow-related deformation structures of the overlying sediments. In this project we apply tectonic field studies in the Southern Maritimes Basin and scaled physical experiments consisting of sand-silicone models with new high-resolution deformation monitoring techniques to study the tectonic evolution and salt mobilization in the Maritimes basin and will provide support for future petroleum exploration in this area.