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    This geological map (1:10.000 scale) of the 'Sassello Basin' remnant covers an area of about 33.4 km2 of Liguria (NW Italy); it highlights the occurrence of two main types of contacts between the sediments of the Tertiary Piedmont Basin and the metamorphic substratum (Voltri Unit): (i) stratigraphic and (ii) structural (thrust or steeply dipping faults). (i) Stratigraphic contacts are represented by the main transgressive surface and the nonconformity between the metamorphic rocks of the substratum and the subaerial deposits. They are locally folded and occur along the steeply dipping short limbs of asymmetric folds related to the late-alpine/apennine tectonics. (ii) Structural contacts are related to the late-alpine/apennine tectonics (thrust faults) or (mostly) to Plio-Quaternary extensional/transtensional faulting.
    Transgressive
    Abstract Brittle structures identified within the largest karstic cave of the Sudetes (the Niedźwiedzia Cave) were studied to reconstruct the paleostress driving post-Variscan tectonic activity in the NE Bohemian Massif. Individual fault population datasets, including local strike and dip of fault planes, striations, and Riedel shear, enabled us to discuss the orientation of the principal stresses tensor. The (meso) fault-slip data analysis performed both with Dihedra and an inverse method revealed two possible main opposing compressional regimes: (1) NE–SW compression with the formation of strike-slip (transpressional) faults and (2) WNW–ESE horizontal compression related to fault-block tectonics. The (older) NE-SW compression was most probably associated with the Late Cretaceous–Paleogene pan-regional basin inversion throughout Central Europe, as a reaction to ongoing African-Iberian-European convergence. Second WNW–ESE compression was active as of the Middle Miocene, at the latest, and might represent the Neogene–Quaternary tectonic regime of the NE Bohemian Massif. Exposed fault plane surfaces in a dissolution-collapse marble cave system provided insights into the Meso-Cenozoic tectonic history of the Earth’s uppermost crust in Central Europe, and were also identified as important guiding structures controlling the origin of the Niedźwiedzia Cave and the evolution of subsequent karstic conduits during the Late Cenozoic.
    Massif
    Neogene
    Lineation
    Lineament
    Abstract The tectonic evolution of the pre-Cenozoic basement, as well as the Cenozoic structures within the Danube Basin (DB) and its northern periphery are presented. The lowermost portion of the pre-Cenozoic basement is formed by the Tatricum Unit which was tectonically affected by the subduction of the Vahicum / Penninicum distal continental crust during the Turonian. Tectonically disintegrated Tatricum overlaid the post-Turonian to Lower Eocene sediments that are considered a part of the Vahicum wedge-top basin. These sediments are overthrust with the Fatricum and Hronicum cover nappes. The Danube Basin Transversal Fault (DBTF) oriented along a NW–SE course divided the pre-Neogene basement of the DB into two parts. The southwestern part of the DB pre-Neogene basement is eroded to the crystalline complexes while the Palaeogene and Mesozoic sediments are overlaid by the Neogene deposits on the northeastern side of the DBTF. The DBTF was activated as a dextral fault during the Late Oligocene – Earliest Miocene. During the Early Miocene (Karpatian – Early Badenian) it was active as a normal fault. In the Middle – Late Miocene the dominant tectonic regime with NW – SE oriented extension led to the disintegration of the elevated pre-Neogene basement under the simple and pure shear mechanisms into several NE – SW oriented horst and graben structures with successive subsidence generally from west to east. The extensional tectonics with the perpendicular NE – SW orientation of the S hmin persists in the Danube Basin from the ?Middle Pleistocene to the present.
    Neogene
    Basement
    Horst
    Paleogene
    Alpine orogeny
    Citations (22)