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Pore pressure field built up in a rapidly eroded soil mass. Note
64 A
Environmental effects, weathering and soil formation See also: 912102
912008 Mobile jet erodibility meter (In French) Henensal, P; Duchatel, F Bull Liaison Labs Ponts Chaussees N167, Ma.v-June 1990, P47-52
A portable erodibility test device is described, which can be applied to surfaces ranging from friable soils to soft rocks. It acts on a circular surface 152ram in diameter. Water runoff, water percolating, and soil eroded are measured. An attempt is made to assess the importance of various parameters affecting erosion rate: jet velocity, soil mechanical proparties, vegetation, and surface compaction.
912009 Pore pressure field built up in a rapidly eroded soil mass. Note Fenelli, G B; Picarelli, L Can Geotech J 1/27, N3, June 1990, P387-392
Shallow slides occur periodically in valleys in the Bisaccia region of the Appennines, generally having the toe in the underlying clay layers. The pore pressure field in the area has been investigated to depths of 5.7m. The unexpected results can be explained in terms of the recent gcomorphological evolution of the area which is subject to rapid erosion, and very low permeability of the clay soils hindering dissipation.
912010 Experimental frost and salt weathering of chalk - I Jerwood, L C; Robinson, D A; Williams, R B G Earth Surf Process Land VI5, N7, Not" 1990, P611-624
Cubes of chalk were immersed separately in solutions of sodium chloride, sodium sulphate, and magnesium sulphate at concentrations 5.5 and 12.5%, in a solution of both sodium salts, and in distilled water. They were then subjected to six cycles of freeze thaw at + 15/-10 deg C or + 15/-30 deg C. The presence of certain salts increases frost weathering, the amount being dependent on type and concentration of salt and intensity of the freeze thaw cycling. Results can be partially explained in terms of phase changes occurring during freezing of the salt solution.
912011 Differential weathering of feldspar and pyroxene in an arcticalpine environment McCarroll, D Earth Surf Process Land V15. N7. Not" 1990. P641.651
Differential relief of adjacent plagioclase and pyroxene minerals was measured on an outcrop of gabbroic rock in Norway using a micro-roughness meter. Feldspars protrude above the pyroxenes above the level of the former soil surface, the reverse being true below this level. Differential relief declines with increasing burial depth. Results indicate a marked change of weathering conditions at the soil/atmosphere interface. Rate controlling factors are discussed. The importance of chemical weathering in arctic/alpine environments is evident.
912012 Soil development rates in the Transantarctic ,Mountains Bockheim. J G Geoderma V47, NIl2, Aug 1990, P59-77
Over 175 soils were sampled on moraines of different ages containing sandstone and dolorite in order to examine rates of soil development in Cold Desert ecosystems. Significant correlations were seen between drift age and soil properties. Soluble salts accumulate steadily in Cold Desert soils in the absence of leaching. Dominant processes in these soils are salinization, reddening due to oxidation of iron-bearing minerals (rubification), and desert pavement formation.
912013 Coordination chemistry of weathering: kinetics of the surfacecontrolled dissolution of oxide minerals Stumm. W; Wollast, R Revs Geophys V28, NI. Feb 1990, P53-69
Chemical weathering processes, the reaction of geological media with the atmosphere and water, have important geological and geotechnical consequences. The weathering process and its rate controlling steps are outlined. Surface reactivity is seen to depend on the surface species and their structural identity. A general rate law for surface controlled dissolution is developed, and the kinetics of the dissolution reactions described.
912014 Polar environment actions on the rubble mound breakwater, support for the Terre Adelie airfield, Antarctica (in French) Regrettier, J F Rev Fr Geotech N53. 1990, P55-65
The 1100m long structure to support the runway at Terre Adelie is under construction, following evaluation of a test embankment, built in 1987. The structure is of gneissic rock rubble, excavated by blasting, and is founded on the seabed. It is subject to wind and wave action, freezing of seawater in the structure in winter, and frost shattering of the rock blocks. The temperature and water level distributions recorded in the test embankment, and measured deterioration of the rock are described.
912015 Changes in the particle size distribution of quartoze sands affected by laterization: an approach by computer simulation Righi, D; Bravard, S; Legros, J P; Falipou, P Soil Sci V149, N6. June 1990, P361.366
Particle size distributions (psd) of sandy fractions separated from an equatorial soil developed from the same parent but with different pedogenesis were studied. Computer simulation was carried out of the transformation of the psd curve of the parent material sandy fraction after dissolution or fragmentation of the sandy grains. Experimental and computed psd curves were compared to examine whether psd of the sandy fraction had changed during pedogenesis, and whether it could be used to identify common origin of strongly weathered materials. It was concluded that psd curves of sand are not an adequate test in tropical soil.
~), 1991 Pergamon Press plc. Reproduction not permitted
Environmental effects, weathering and soil formation See also: 912102
912008 Mobile jet erodibility meter (In French) Henensal, P; Duchatel, F Bull Liaison Labs Ponts Chaussees N167, Ma.v-June 1990, P47-52
A portable erodibility test device is described, which can be applied to surfaces ranging from friable soils to soft rocks. It acts on a circular surface 152ram in diameter. Water runoff, water percolating, and soil eroded are measured. An attempt is made to assess the importance of various parameters affecting erosion rate: jet velocity, soil mechanical proparties, vegetation, and surface compaction.
912009 Pore pressure field built up in a rapidly eroded soil mass. Note Fenelli, G B; Picarelli, L Can Geotech J 1/27, N3, June 1990, P387-392
Shallow slides occur periodically in valleys in the Bisaccia region of the Appennines, generally having the toe in the underlying clay layers. The pore pressure field in the area has been investigated to depths of 5.7m. The unexpected results can be explained in terms of the recent gcomorphological evolution of the area which is subject to rapid erosion, and very low permeability of the clay soils hindering dissipation.
912010 Experimental frost and salt weathering of chalk - I Jerwood, L C; Robinson, D A; Williams, R B G Earth Surf Process Land VI5, N7, Not" 1990, P611-624
Cubes of chalk were immersed separately in solutions of sodium chloride, sodium sulphate, and magnesium sulphate at concentrations 5.5 and 12.5%, in a solution of both sodium salts, and in distilled water. They were then subjected to six cycles of freeze thaw at + 15/-10 deg C or + 15/-30 deg C. The presence of certain salts increases frost weathering, the amount being dependent on type and concentration of salt and intensity of the freeze thaw cycling. Results can be partially explained in terms of phase changes occurring during freezing of the salt solution.
912011 Differential weathering of feldspar and pyroxene in an arcticalpine environment McCarroll, D Earth Surf Process Land V15. N7. Not" 1990. P641.651
Differential relief of adjacent plagioclase and pyroxene minerals was measured on an outcrop of gabbroic rock in Norway using a micro-roughness meter. Feldspars protrude above the pyroxenes above the level of the former soil surface, the reverse being true below this level. Differential relief declines with increasing burial depth. Results indicate a marked change of weathering conditions at the soil/atmosphere interface. Rate controlling factors are discussed. The importance of chemical weathering in arctic/alpine environments is evident.
912012 Soil development rates in the Transantarctic ,Mountains Bockheim. J G Geoderma V47, NIl2, Aug 1990, P59-77
Over 175 soils were sampled on moraines of different ages containing sandstone and dolorite in order to examine rates of soil development in Cold Desert ecosystems. Significant correlations were seen between drift age and soil properties. Soluble salts accumulate steadily in Cold Desert soils in the absence of leaching. Dominant processes in these soils are salinization, reddening due to oxidation of iron-bearing minerals (rubification), and desert pavement formation.
912013 Coordination chemistry of weathering: kinetics of the surfacecontrolled dissolution of oxide minerals Stumm. W; Wollast, R Revs Geophys V28, NI. Feb 1990, P53-69
Chemical weathering processes, the reaction of geological media with the atmosphere and water, have important geological and geotechnical consequences. The weathering process and its rate controlling steps are outlined. Surface reactivity is seen to depend on the surface species and their structural identity. A general rate law for surface controlled dissolution is developed, and the kinetics of the dissolution reactions described.
912014 Polar environment actions on the rubble mound breakwater, support for the Terre Adelie airfield, Antarctica (in French) Regrettier, J F Rev Fr Geotech N53. 1990, P55-65
The 1100m long structure to support the runway at Terre Adelie is under construction, following evaluation of a test embankment, built in 1987. The structure is of gneissic rock rubble, excavated by blasting, and is founded on the seabed. It is subject to wind and wave action, freezing of seawater in the structure in winter, and frost shattering of the rock blocks. The temperature and water level distributions recorded in the test embankment, and measured deterioration of the rock are described.
912015 Changes in the particle size distribution of quartoze sands affected by laterization: an approach by computer simulation Righi, D; Bravard, S; Legros, J P; Falipou, P Soil Sci V149, N6. June 1990, P361.366
Particle size distributions (psd) of sandy fractions separated from an equatorial soil developed from the same parent but with different pedogenesis were studied. Computer simulation was carried out of the transformation of the psd curve of the parent material sandy fraction after dissolution or fragmentation of the sandy grains. Experimental and computed psd curves were compared to examine whether psd of the sandy fraction had changed during pedogenesis, and whether it could be used to identify common origin of strongly weathered materials. It was concluded that psd curves of sand are not an adequate test in tropical soil.
~), 1991 Pergamon Press plc. Reproduction not permitted