Pages: 211 - 221
Abstract: The NW-SE striking Myto-Tisovec map-scale brittle fault distinctively affects the internal zones of the Western Carpathians. It cuts and evidently offsets Meso-Alpine tectonic units and structures and represents a zone of important geophysical anomalies as well. Using methods of structural analysis, the complex tectonic evolution of this long living fault has been restored. Six successive fault-slip related regional paleostress events, controlling the activity of the Myto-Tisovec fault have been distinguished. The oldest recognized paleostress event, with NNE-SSW maximum principal stress axis operated after the Late Cretaceous and before the Middle Eocene. The orientation of the Miocene maximum principal stress axis rotated clockwise from NW-SE in the Early Miocene to a NE-SW direction in the Middle Miocene and E-W direction in the Late Miocene–Pliocene. NNW-SSE trending compression has been estimated for the Quaternary stress field. Correspondingly, three periods of Miocene tensional paleostress events with NE-SW, NW-SE and N-S orientation of minimum principal stress axis has been restored as well. The Myto-Tisovec fault kinematically fluctuated in the changing paleostress field. However, the most evident structural records are related to the dominant dextral strike-slip regime. Dextral transtensional tectonic regime was responsible also for opening of a narrow and deep depositional depression — the Brezno Basin, related to the Myto-Tisovec fault, where the Late Eocene–Early Miocene sediments of the Central Carpathian Paleogene Basin (CCPB) fill have been deposited and later preserved.
Keywords: Tertiary, Western Carpathians, structural evolution, paleostress analysis, faultsDownload PDF document Show Text Version