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  • Gully erosion ; Hungary ; Sandstone ; Soil erosion
  • The Medves Region is a small landscape unit in North Hungary. Its rocks originated in the Tertiary era, among others Oligocene-Miocene sandstones are very typical. The erosional forms of these sandstones are peculiar, especially the sandstone
  • Sandstone dissolution landforms in the Furnas Formation, Southern Brazil
  • Brazil ; Carbonate dissolution ; Erosion ; Fault ; Geological structure ; Kaolinite ; Karst ; Paraná ; Sandstone ; Sedimentary
  • The Furnas Formation (Silurian to Devonian of the Paraná Basin) consists of medium to coarse sandstones cemented by kaolinite, which reduces its porosity and makes the rock more resistant. The findings indicate that the great features
  • Geostatistical analysis in weathering studies : case study for Stanton Moor building sandstone
  • Geostatistics ; Grain size distribution ; Permeability ; Sandstone ; Simulation ; Spatial variation ; United States of America ; Weathering
  • ) and diagenetic processes on permeability variation will be investigated for Stanton Moor Sandstone.
  • Experimental frost weathering of sandstone by various combinations of salts
  • Experimentation ; Freeze-thaw cycle ; Freezing ; Gypsum ; Salt ; Sandstone ; Weathering
  • Weathering experiments are reported combining frost and a range of salts that occur widely on sandstone rock outcrops in western and central Europe. The effects of alunogen, gypsum, halite and alum salts are examined, both singly and in combination
  • Weathering basins in the Clarens Formation Sandstone, South Africa
  • Mineralogy, petrography and structures of iron crusts (ferricretes) developed on sandstones in the western part of Senegal
  • Origin of minor sandstone landforms
  • Salt distribution in clay-rich weathered sandstone
  • Clay mineral ; Geochemistry ; Oceanic climate ; Porosity ; Salt ; Sandstone ; Temperate zone ; Urban area ; Weathering
  • Analysis of two clay-rich sandstone blocks from a temperate maritime, urban environment indicates that, although structural changes such as scaling and flaking affect only the outer 10-20 mm of stone, the zone of alteration extends well beyond
  • variable sandstone, differences in porosity and/or clay mineral may result in different blocks being more susceptible to decay than other blocks.
  • A geostatistical investigation into changing permeability of sandstones during weathering simulations
  • Erosion rate ; Geostatistics ; Geotechnics ; Mid-latitude climate ; Model ; Northern Ireland ; Permeability ; Salt ; Sandstone ; Simulation ; United Kingdom ; Weathering
  • The aim of this research is to improve the understanding of the decay dynamics of masonry materials and sandstone by weathering and to provide a quantitative and predictive basis for conceptual models of sandstone decay using geostatistics. Data
  • Calcium loading of quartz sandstones during construction : implications for future decay
  • Atmospheric pollution ; Building materials ; Chemical erosion ; Gypsum ; Permeability ; Sandstone ; United Kingdom ; Weathering
  • Damage to quartz sandstones in polluted urban environments is frequently associated with the presence of calcium salts, especially gypsum. The aim of this study is to examine the possibility that non-calcareous quartz sandstones can be loaded
  • Age and hydrological significance of lichen limits on sandstone river channels near Sydney, Australia
  • Australia ; Drought ; Flood ; Hydrology ; Lichen ; Lichenometry ; New South Wales ; Plant colonization ; River regime ; Sandstone ; Stream
  • of flow regulation and climate change. They can also be used to set flushing flows in bedrock channels. In sandstone gorges of the Nepean River, Australia, the crustose lichen,Lecidea terrena Nyl, was common at both gorge and cemetery (sandstone headstones
  • ) sites, enabling construction of growth curves for above and below dam areas. Growth curves were used to date lichen colonisation of sandstone surfaces in rivers. It is showed that lichens colonised exposed sandstone between the level of frequent flows
  • Sandstone weathering in the High Atlas, Morocco
  • Atlas Mountains ; Morocco ; Periglacial features ; Sandstone ; Sedimentary ; Semi-arid area ; Weathering
  • Contour scaling of a sandstone by salt weathering under simulated hot desert conditions
  • Surface disaggregation and essentially surface-parallel cracks were produced in sandstone blocks using 10 per cent solutions of sodium sulphate and magnesium sulphate applied daily to single exposed surfaces for sixty days. A control block soaked
  • The weathering rates of some sandstone cliffs, central Weald, England
  • Short-term (1-30 months) weathering rates were obtained for steep cliffs of Cretaceous Ardingly Sandstone in southern England, using a new photographic method. There was no correlation with grain size, porosity, or mean surface temperature. Highest
  • Comparative study ; Erosion ; Instrumentation ; Japan ; Kyushu ; Research technique ; Sandstone ; Weathering
  • Tafone-like depressions have developed on the Aoshima sandstone blocks used for a masonry bridge pier in the coastal spray zone. To evaluate quantitatively the strength of the thin weathered layer, the hardness was measured at the surface
  • of the sandstone blocks using both an Equotip hardness tester and an L-type Schmidt hammer. This article first describes the results, and secondly evaluates the usefulness of the device in quantifying the degree of rock weathering.
  • Alberta ; Badland ; Canada ; Duricrust ; Geochemistry ; Lithology ; Rill wash ; Sandstone ; Water erosion ; Watershed ; Weathering
  • Rill systems on mudrock and sandstone in Alberta badlands were studied to examine progressive changes in material properties as smectic-rich mudrocks and sandstones undergo weathering, and the impact of seasonal changes in precipitation patterns
  • Processes and rate of retreat of the clay and sandstone sea cliffs of the northern Boulonnais (France)
  • Retreat of the clay and sandstone cliffs of the northern Boulonnais has been quantified using stereo photogrammetry. The low retreat rate of this coastal strip is far less than that encountered on chalk and clay-chalk cliffs of either side
  • Coeval biochemical and biophysical weathering processes on Quaternary sandstone terraces south of Rabat (Temara), northwest Morocco
  • Biogenic process ; Lichen ; Microstructure ; Model ; Morocco ; Quaternary ; Sandstone ; Terrace ; Weathering
  • Geomorfologicka analyza mereni dilata piskovcovych bloku v udoli Libechovky, Polomené hory. (Geomorphological analysis of sandstone block dilatations in the Libechovka valley, Polomené Hills))
  • Long term dilatations in vertical fissures between sandstone blocks are confronted with the geomorphological development of the rock relief in the low Libechovka valley between Tupadly and Zelizy in the Polomené Hills. The measurement diagrams
  • Biofilms and case hardening on sandstones from Al-Quwayra, Jordan
  • Arid area ; Biogenic process ; Electron microscope ; Geochemistry ; Inselberg ; Jordan ; Micromorphology ; Rock ; Sandstone ; Taffoni