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  • Liesegang blocks from sandstone beds of the Hojedk Formation, Kerman, Iran
  • Drainage ; Geochemistry ; Iran ; Microstructure ; Sandstone ; Tectonics ; Weathering
  • In this paper, three types of Liesegang blocks from sandstone beds of the Hojedk Formation are described. The factors involved in their formation, and their tectonic implication are discussed.
  • Weathering rates of Tertiary sandstone and mudstone in Japan
  • Cenozoic ; Erosion rate ; Honshu ; Japan ; Marine terrace ; Sandstone ; Sedimentary rock ; Tokyo ; Weathering
  • , Japan. The bedrock of terraces consists mainly of Tertiary sandstone and mudstone. The mode of deceleration in the weathering rates with time differs between mudstone and sandstone. Initially mudstone weathers faster than sandstone, but the mudstone
  • weathering rate decreases more rapidly than sandstone, and after about 400 years, the sandstone rate exceeds that of mudstone.
  • Weathering of a Tassili Silurian sandstone, Central Sahara. Preliminary report
  • The physical and mechanical properties of the Fell Sandstones, Northumberland, England
  • Conical sandstone landforms cored with clastic pipes in Glen Canyon National Recreation Area, southeastern Utah
  • Arid area ; Differential erosion ; Sandstone ; United States of America ; Utah ; Weathering ; Wind erosion
  • Clusters of conical sandstone landforms, many with summit weathering pits, have developed on barren outcrops of the Jurassic Entrada Sandstone in Glen Canyon National Recreation Area. The conical landforms have developed on cylindrical bodies
  • of fluidized sandstone (clastic pipes) that typically have near-vertical contacts with the enclosing cross-bedded, eolian sandstone. These landforms vary in size and shape due chiefly to differential erosion of the clastic pipe relative to the enclosing
  • sandstone. The resistant rims of these pits are due in part to calcite-enriched pipe contacts. Sandy pit-floor sediment is removed principally by strong wind rotors and vortices.
  • Sandstone weathering thresholds in Petra, Jordan
  • Arid area ; Insolation ; Jordan ; Lithology ; Sandstone ; Statistics ; Threshold ; Weathering
  • The primary focus of this investigation was to examine the various mechanisms and rates responsible for sandstone weathering in an arid climate by controlling lithology, time, and the initial surface condition. However, the possible existence
  • Experimental weathering of sandstone by combinations of salts
  • Chemical erosion ; Experimentation ; Geochemistry ; Salt ; Sandstone ; Weathering
  • Laboratory experiments are described that examined the effectiveness of certain naturally occurring combinations of salts as weathering agents. Cubes of a highly quartzose sandstone were repeatedly soaked in one of a series of salt solutions
  • Mechanism and rate of weathering of Clarens sandstone by an endolithic lichen
  • An endolithic lichen was discovered actively eroding sandstone at a rate of 9.6 mm/100 years - three times faster than had previously been accurately measured.
  • Skalni hriby v pislovcich Broumovské vrchoviny. (Mushroom rocks in sandstones of the Broumovska vrchovina (Highland))
  • Regional distribution and the morphogenesis of mushroom rocks in the Upper cretaceous block sandstones of the Broumovska vrchovina Highland (NE Bohemia). (MS).
  • Sandstone response to salt weathering following simulated fire damage : a comparison of the effects of furnace heating and fire
  • Chemical erosion ; Derbyshire ; England ; Fire ; Geotechnics ; Salt ; Sandstone ; Simulation ; United Kingdom ; Weathering
  • To explore the differences between heating sandstone in a furnace and a real fire, sample blocks of Peakmoor Sandstone, quarried from Matlock in Derbyshire, were subjected to different stress histories in combination (lime rendering and removal
  • Rates of rock property changes due to weathering : sandstone gravel in fluvial terrace deposits in the Miyazaki Plain
  • Fluvial terrace ; Geochemistry ; Japan ; Kyushu ; Leaching ; Lithology ; Mineralogy ; Palaeogeography ; Porosity ; Sandstone ; Weathering
  • Temporal changes in colour, mineralogical, chemical, physical and mechanical properties due to weathering during 350,000 years were examined using sandstone gravel in fluvial terrace deposits with a known emergence time which were distributed
  • in the Miyazaki Plain, South Kyushu. The results suggest that leaching of matrix and increasing pore volume plays a major role in the weathering of sandstone.
  • Die ontstaan van grotte en holtes in die kranse van die Clarenssandsteenformasie in die Golden Gategebied. (The origin of the caves and hollows in cliffs of the Clarens sandstone formation in the Golden Gate area.)
  • The origin of the caves and hollows could be ascribed to the following mechanisms: exudation, undermining of the sandstone by faster weathering of the sandstone below, faster weathering of shale or clay-bearing sandstone layers in the sandstone
  • and the solution of lime concretions in the sandstone. Exudation is probably the most important factor. An analysis of a sample of salt collected in a cave showed that the active exudation agents are sodium carbonate and sodium sulphate. With the exception
  • Gypsum formation in non-calcareous building sandstone : a case study of Scrabo sandstone
  • Atmospheric pollution ; Belfast ; Building materials ; Chemical erosion ; Mineralogy ; Northern Ireland ; Sandstone ; United Kingdom ; Weathering
  • This paper addresses one central issue of building stone research : an origin for calcium in gypsum formation in non-calcareous sandstones. A comparative study of Scrabo sandstone from outcrops and a 120-year-old building in central Belfast shows
  • Ferruginous sandstone for building-stone in and round the Hageland
  • Belgium ; Building materials ; Inventory ; Natural resources ; Quarry ; Rock ; Sandstone
  • Ferruginous sandstone has locally been used extensively in mostly late-medieval religious and civilian architecture. An inventory of recognizable exploitation sites is presented. Genesis and related characteristics of the different types of building
  • Composition and genesis of the ferruginous sandstones of the Diest and the Poederlee Formations (Belgium)
  • Mineralogical and chemical study has shown that the genesis of the sandstones cannot be explained by a weathering in situ of Fe-bearing minerals or by other pedogenetic processes. The strong relative increase of Fe against Al, compared to the values
  • Triassic palynology of the Warang Sandstone (Northern Galilee Basin) and its phytogeographic implications in Gondwana Five. Selected papers and abstracts of papers.
  • Australie ; Dérive des continents ; Galilee Basin ; Gondwana ; Géographie de l'Océanie ; Mésozoïque ; Palynologie ; Paléobiogéographie ; Paléogéographie ; Trias ; Warang Sandstone
  • Namib sandstone: a distinct lithological unit
  • The Namib Sandstone is a consolidated rock deposit with considerable surface extent. It underlies and extends beyond the present Namib dune field. It provides a source for the Namib sands and is of importance in any analysis of the Namib's
  • The Quaternary sculpturing of sandstones in the Rusavská hornatina Mts.
  • Czech Republic ; Holocene ; Mountain ; Periglacial features ; Periglacial landform ; Pleistocene ; Quaternary ; Sandstone
  • 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