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Landslides in the West Carpathians
Published in Jan Rybář, Josef Stemberk, Peter Wagner, Landslides, 2018
The Outer Flysch belt creates robust ranges of mountains consisting of the Cretaceous and Paleogene flysch strata in several facial developments. The most characteristic is a fine rhytmic flysch with alternating rather thin benches (centimeters to some meters) of shale, conglomerate and sandstone, and a thick-bedded flysch in which thick (meters to some deca meters) layers of sandstone prevail. Matula (1969) distinguished the areas of the Flysch Highlands and the Flysch Uplands. The Flysch Highlands, with moderately shaped ridges, reach the height of 900 to 1700 m, and relative heights of 500 to 600 m. Subsequent valleys and washouts developed. Even steeper ridges or monoclinal ridges on sandstone beds developed, often cut by narrow transverse valleys. Quaternary slope deposits consist mostly of clayey sandy loam, and sometimes of debris under steep sandstone rock walls. The conditions in the Flysch Uplands are very similar to those in highlands. A fine rhytmic flysch with predominantly shale prevails and the mountain height reach up to 500 to 1000 m a.s,l., and the relative height of 150 to 300 m. Clayey loams reach up to 5 to 8 m on the toe of slopes.
Eastern Adriatic
Published in Enzo Pranzini, Allan Williams, Coastal Erosion and Protection in Europe, 2013
Kristina Pikelj, Vojislav Dragnić, Nemanja Malovrazić
shape and lengths are irregular, whether on the mainland or on islands, and they are strongly influenced by local coastal geomorphology. Flysch coasts As stated, coasts cut in flysch deposits are less common compared to limestone coasts, all outcrops being of Eocene age (alternate marls, siltstones and sandstones sequences, making soft, easily weathered rock systems), except in Budva-Bar, where they are of Triassic age. Flysch zones stretch along the entire Slovenian coast; whilst in Croatia there are flysch outcrops on Krk and Rab Islands, in the Zadar hinterland, in the Split-Ploc e belt and south of Dubrovnik. In Montenegro, flysch coasts dominate in the Bar-Ulcinj belt (Figure 16.1). Badlands are a common erosional landscape on the flysch and cliffed coasts evolve under destructive wave impact and subaerial weathering and erosional processes. Due to its mixed lithology, flysch does not erode at similar rates. Cliffs are usually formed in the more resistant sandstones, while rockfalls, earth flows and mass movements are commoner in the less resistant marls (Jurac ic et al., 2009). This is especially true for ' Slovenian cliffs, which are particularly well developed in the Piran and Strunjan areas (Figure 16.8). These cliffs are convex-to-steep cliff types, rimmed by
Diagenesis and Properties of Sedimentary Rocks
Published in Aurèle Parriaux, Geology, 2018
Flyschs (Fig. 10.10) are detrital rocks formed in the ocean from deposits that were originally deep sea fans caused by orogenic movements (Chapt. 9). In the Alps, flyschs have been tectonically transported by thrust sheets (Chapt. 12). The term flysch includes sandstones and siltstones alternating with claystones, rocks that are characteristic of a turbidite sedimentary cycle. The sandstones are not very porous and occur in benches that are decimeters thick. They are good for construction and road pavement. The intercalated claystones promote landslides on slopes.
Mapping landslide susceptibility at national scale by spatial multi-criteria evaluation
Published in Geomatics, Natural Hazards and Risk, 2021
Adrian Grozavu, Cristian Valeriu Patriche
The orogen unit comprises: 1) The Romanian Carpathian Mountains (maximum elevation: 2544 m) – spread out in the shape of a circular arc in the center of the country, consisting of crystalline formations, volcanic rocks and flysch sedimentary formations. In the Oriental Carpathians, where geological formations are arranged in parallel strips, the volcanic chain occupies their western part and it is made up mainly of andesites and volcanic conglomerates. The Paleogene flysch area is present in the eastern part of the Oriental Carpathians and in the Curvature Carpathians and it is represented mainly by clay schists, limestones, conglomerates, sandstones, marlstones, intensely folded within nappes. 2) The Transylvanian Depression – is situated inside the Carpathian arc, it has a tectonic origin (being subjected to a sinking process since the end of the Mesozoic era) and its sedimentary fill includes volcanic tuffs, salt formations, marlstones, clays and sands. 3) The peri-Carpathic Hills (Subcarpathians) – border the Carpathians towards east and south and they are developed on folded Neogene mollase formations (sandstones, clays, marlstones, gravels, gyps and salt formations). The Getic Plateau is also included here, situated in the south of Subcarpathian sector with the same name, being consisting of Pliocene and Quaternary strata (mainly gravels and sands) with monocline structure. 4) The Western Hills and Plain – occupy the western part of the country, overlapping the edge of the Pannonian Basin (formed at the same time as the Transylvanian Depression) and it consists of sedimentary formations (clays, marls, gravels and sands) of Pliocene and Quaternary age.