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  • Borehole failures in crystalline rocks of South-Western Nigeria
  • Aquifer ; Crystalline rocks ; Fault ; Geotechnics ; Hydrogeology ; Nigeria ; Piezometric level ; Seasonal variation ; Sounding ; Water resources
  • The aim of this study is therefore to identify the factors causing boreholes failures in the crystalline rocks of the basement complex and recommend strategies to overcome these factors.
  • Magyarorszag legosibb kristalyos kozetei és kapcsolatuk a kazpati-alpi hegységkerettel. (Most ancient crystalline rocks in Hungary and their relation to the Carpathian-Alpine mountain frame)
  • The most ancient rocks in Hungary are crystalline schists and igneous intrusives approximately five hundred million years old. Similar rocks can be detected along SW-NE axes partly on the surface and partly in the basement. Much of ancient rocks
  • Characterisation of channel network structures in crystalline and granite rock groups of Almora Nappe
  • Weathering processes on rock surfaces in the Hunza Valley, Karakoram, North Pakistan
  • Crystalline rocks ; Duricrust ; Erratic boulder ; Karokoram ; Moraine ; Pakistan ; Valley ; Weathering
  • This paper reports on rock temperature fluctuation in the north and south surfaces of a moraine boulder in Hunza Karakoram obtained over 2 years, and concludes that the rock surface weathering processes depend primarily on the differences
  • of the rock temperatures due to orientation.
  • The denudation history of the Argentera alpine external crystalline massif (Western Alps, France-Italy) : an overview from the analysis of fission tracks in apatites and zircons
  • Alps (The) ; Crystalline rocks ; Dating ; Erosion ; Europe ; Geochemistry ; Model ; Neogene ; Tectonics ; Vertical movement
  • This study presented here is based on fission tracks analyses of apatites and zircons from 32 new samples of the Argentera external crystalline massif (Western Alps) and discusses the structural, kinematic and thermal implications in order
  • Groundwater exploration in crystalline rocks in Africa
  • Surface temperature differences between minerals in crystalline rocks : implications for granular disaggregation of granites through thermal fatigue
  • Albedo ; Crystalline rocks ; Granite ; Insolation ; Lithology ; Surface temperature ; Temperature ; Weathering
  • This work confirms the exixtence of surface temperature differences between minerals in granitic rocks under simulated short-term temperature fluctuations so as to discriminate their potential for initiating granular disaggregation. The influence
  • of colour, as a surrogate for albedo, and crystal size, as a function of thermal mass are specifically identified because of their ease of quantification. Four rock types with a range of these properties were examined, and subjected to repeated short-term
  • Intense karst denudation in a crystalline basin with a small share of carbonate rocks (Sudety Mountains, SW Poland)
  • Carbonate dissolution ; Carbonate rock ; Erosion rate ; Hydrochemistry ; Karst ; Marble ; Poland ; Sudety ; Watershed
  • by non-carbonate crystalline metamorphic rock. Marble corrosion is caused primarily by the influx of allogenic waters from the non-carbonate part of the catchment. Hydrochemical measurements were made over the course of 8 years. The calculated denudation
  • Biogenic action;Biogenic process ; Crystalline rocks ; Vegetation ; Weathering
  • Evidence is presented suggesting that micro-vegetation, notably lichens, substantially influences the weathering of the material on which it grows. Changes on two rock types are examined in order to assess the role of lichens in the mechanical
  • Nappe stacking and first evidence of Late Variscan extension in the Belledonne Massif (External Crystalline Massifs, French Alps)
  • Alps (The) ; Crystalline rocks ; France ; Microstructure ; Mountain ; Orogeny ; Palaeozoic ; Regional geology ; Tectonic thrust ; Tectonics
  • Inherited landforms in the crystalline areas of the Sudetes Mts. A case study from the Jelenia Gora basin, SW Poland
  • Cenozoic ; Climatic variation ; Crystalline rocks ; Geomorphogenesis ; Inherited features ; Inselberg ; Lithology ; Poland ; Sudety ; Tectonics
  • Development of gullies under forest cover in the Taunus and crystalline Odenwald mountains, Germany
  • Agricultural practice ; Crystalline rocks ; Forest ; Germany ; Gully erosion ; Hessen ; Historical geography ; Land use ; Mountain ; Rill wash ; Slope
  • Rock slopes of the High Tatras mountains
  • Geomorphogenesis ; Glacial features ; Mountain ; National park ; Periglacial features ; Rock ; Slope ; Slovak Republic ; Structural geomorphology ; Tatra Mountains
  • Substantial part of the alpine relief of the High Tatra is composed of rock slopes. Geomorphological analysis shows that the development of high rock slopes on crystalline rocks is guided, in principal, by their morphostructural position
  • The aim of this study is to determine the behavior of REE, U and Th during the weathering of a crystalline rock with common REE-U-Th contents. The Akongo lateritic profile which developed on a syenite has been chosen because 1) this profile
  • is representative of the main lateritic profiles found in tropical environments, 2) the possibility to calculate mass balance in the crystalline parent rock and 3) the contrasted behavior of elements during lateritic weathering.
  • A computer simulation approach to textural interpretation in crystalline rocks in Recent advances in geomathematics. An international symposium.
  • Crystalline rocks ; Geomorphology ; Granite ; Portugal ; Structural geomorphology ; Weathering
  • Crystalline rocks ; Devon ; England ; Geomorphology ; Grain size distribution;Granulometry ; Granites ; Petrology ; United Kingdom
  • The purpose of this analysis is to better characterize landforms composed of granitic rock. Dartmoor was selected for study because of its classic suite of landforms. This paper presents a semiquantitative classification of the Dartmoor tors based
  • Antarctica ; Cold area ; Crystalline rocks ; Electron microscope ; Mountain ; Petrology ; Weathering
  • The weathering of granodiorite porphyry is examined in the extremely cold and dry environment of the inland part of Antarctica. Weathering features include granular disintegration, rock varnish, and sheeting. Sheeting has gradually proceeded since
  • the exposing of the nunatak, but the other types of weathering have not actively advanced in recent times. Sheeting has precipitated rock falls, and has gradually formed a gray mosaic on the varnished wall. The sheeting was caused by gravitational body force
  • , which is internal stress of the rock body due to the mass of the oberburden.
  • Long-term isovolumetric leaching of aluminium from rocks during weathering : implications for the genesis of saprolite
  • Acid rain ; Aluminium ; Brazil ; California ; Crystalline rocks ; Geochemistry ; Leaching ; Palaeo-environment ; Pedogenesis ; South Carolina ; United States ; Weathering
  • The purpose of this paper is to present isovolumetric geochemical analyses of saprolites (residual soils in which the texture and structures of parent rocks are preserved). In light of the emerging problems of acid rain and Al toxicity
  • Development of joint-controlled rock basins in Bohus granite, SW Sweden
  • Crystalline rocks ; Fracture ; Geomorphogenesis ; Glacial erosion ; Granite ; Photointerpretation ; Rock basin ; Structural geomorphology ; Sweden ; Tectonics ; Weathering
  • The granite area of Bohuslän is characterised by an abundance of rock basins of different sizes. These basins were measured, described and classified from air-photos according to their length, width, area, altitude, shape, boundaries, openness
  • of the basins. The AA. also aim to discriminate between glacial and non-glacial component in rock basin development and to demonstrate the degree of rock control upon morphology in the formerly glaciated area.