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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. [ABSTRACT FROM AUTHOR]

Detailed geological mapping and structural analysis of Niedźwiedzia Cave (in the Orlica-Śnieżnik Dome, NE Bohemian Massif, Central Europe) provides new insights into proto-conduit formation in karstic drainage. Mapping has allowed us to document the structure of Variscan-age foliation and non-outcropping, post-Variscan fault zones at meter-scale resolution. The resulting data has been used to build a detailed 3D model of the marble lens hosting the cave, allowing us to define the primary structural guidance trends. We observe that karst development has been controlled by WSW-ENE trending sub-vertical faults and fractures, with N-S to NNW-SSE steeply dipping foliation playing a subsidiary role. Based on micro-movement sensors in the cave and other neotectonic indicators, and the relationship between structural discontinuities and topography, we propose that structural discontinuities have only become favorable for karst development under Alpine stress conditions, with little or no influence of exhumation relaxation. Furthermore, Variscan foliation in the marble only appears to become relevant in karst guidance in mature stages of karst development, with foliation parting, and in the absence of significant faulting or fracturing. This pattern is only disrupted in the presence of tectonic brecciation or comminution along faults or fractures. Structural guidance in the development of the Niedźwedzia Cave has been further modulated by water-table evolution in the overlying Kleśnica river valley. The result is a cave with three distinct water-table controlled levels and a map pattern of passages that grades from a mature N-S dominated orientation in the south (upstream) to a grid-like arrangement in the younger northern segment of the cave (downstream). • Subsurface mapping of Niedźwiedzia Cave provided new insights into karstic drainage formation. • The subsurface high-resolution mapping revealed non-outcropping lower-order structures. • Structures have only become favorable for speleogenesis under Alpine stress conditions. [ABSTRACT FROM AUTHOR]

Dancing mania is a clinical and cultural phenomenon which occurred in Western Europe between 13th and 18th centuries. The term dancing mania is derived from the Greek words choros, a dance, and mania, a madness. An Italian variant was known as tarantism as victims were believed to have been bitten by tarantula spider. Although symptoms of dancing manias were well documented in contemporary writings the exact aetiology of dancing plaques is still unclear. Several causes for dancing mania have been postulated: demonic possession, the bite of tarantula, ergot poisoning, epilepsy, mass hysterias, exotics religious cults. The article contains a review of hypothesis of epidemic dances included both medical and psychological factors.