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Characteristics and significance of pre-Wisconsinan saprolites in the northern Appalachians : discussion
  • Characteristics and significance of pre-Wisconsinan saprolites in the northern Appalachians : discussion
  • Appalachian Mountains ; Béryllium ; Canada ; Cénozoïque ; Datation ; Gaspésie ; Géochimie ; Paléogéographie ; Québec ; Saprolite ; Stratigraphie ; Zone froide
  • Discussion on the article of Bouchard and Pavich (1989) « on the characteristics and significance of pre-Wisconsinan saprolites in the northern Appalachians », published in a special volume of « Zeitschrift für Geomorphologie » dedicated
  • to saprolites in high latitudes. The first comments deal with local geological matters, including the scientific literature, the geological setting in the field, the misidentification of the nature and origin of sediments overlying the saprolites. Further
Granitic saprolites : their characteristics, identification and influence on soil properties in the Appalachian region of Canada in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • Granitic saprolites : their characteristics, identification and influence on soil properties in the Appalachian region of Canada in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des
  • Caractérisation des propriétés minéralogiques des saprolites, discussion des méthodes utilisées pour identifier ces saprolites et discussion de l'influence du matériau saprolitique sur les propriétés du sol dans cette région.
Weathering and weathering residuals on the Canadian Shield
  • A study of the distribution and characteristics of saprolites on the southeast section of the Canadian Shield showed that a close relationship exists between bedrock lithology, site of the saprolite by respect to local iceflow direction, and its
  • thickness. Since absolute dating methods of saprolites are not yet operational, not very reliable relative dating criteria had to be applied.
Saprolite remnants as indicators of pre-glacial landform genesis in southeast Sweden
  • Saprolite remnants as indicators of pre-glacial landform genesis in southeast Sweden
  • Bloc erratique ; Distribution spatiale ; Fluvioglaciaire ; Glaciaire ; Héritage géomorphologique ; Modèle numérique de terrain ; Météorisation ; Néogène ; Paléogéographie ; Saprolite ; Suède
  • The AA. focus on 26 encountered sites with remnants of gravelly saprolites (grus). The main purpose is to ascertain their association with bedrock forms and implications for the genesis of the bedrock hills. The present distribution of saprolites
Saprolites and related materials in Québec in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • Saprolites and related materials in Québec in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • Dans les saprolites et régolites du Québec, l'altération des minéraux n'a pas toujours atteint les stades les plus avancés et on retrouve ainsi des altérites à dominance de minéraux gonflants. Les conditions du milieu, spécialement celles qui
  • contrôlent le lessivage des cations, sont particulièrement importantes ici. L'existence de saprolites plus ou moins altérés permet de croire que certains ont pu se développer pendant des périodes interglaciaires. La découverte et l'exploitation de l'or dans
  • des saprolites fortement altérés démontrent l'intérêt économique d'une prospection détaillée de ces matériaux.
Weathering in the Wyborg rapakivi area, south-eastern Finland
  • Field survey of weathering sites in the Wyborg rapakivi area indicates that saprolites are far more common in the central part of the massif than in the marginal areas. Many till-covered saprolites and parautochthonous crust-tills prove
  • the weathering to be of preglacial origin. The rapakivi saprolites are of grus type. The weathering has caused both mechanical and chemical alteration of the parent rock. The residual topography comprises small tor-like features.
ALTERATION OF MICAS IN THE SAPROLITE OF A PROFILE FROM ANGOLA. A MORPHOLOGICAL STUDY
  • ALTERATION OF MICAS IN THE SAPROLITE OF A PROFILE FROM ANGOLA. A MORPHOLOGICAL STUDY
  • ANGOLA ; FORMATIONS SUPERFICIELLES ; Géographie physique ; METEORISATION ; MICA ; SAPROLITE ; ZONE INTERTROPICALE
  • REDISTRIBUTION DU FER DANS LE SAPROLITE DUE AUX MOUVEMENTS D'EAU D'UNE NAPPE FLUCTUANTE. INDIRECTEMENT CECI PERMET DE CONCLURE QUE LA TRANSFORMATION PSEUDOMORPHE EN GOETHITE A EU LIEU DANS DES CONDITIONS D'UN BON DRAINAGE ANTERIEUR. (L'A.).
The clay mineralogy and age of deeply weathered rock in north-east Scotland in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • The clay mineralogy and age of deeply weathered rock in north-east Scotland in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • This paper is concerned with the clay mineralogy of the saprolites and its bearing on the problem of dating the period or periods under which the weathering took place. Data for 29 sites on the clay mineralogy of saprolites in different rock types
Importance paléogéomorphologique et paléogéographique des altérites à saprolites pour l'étude de la formation du relief des montagnes dans le sud de la Bulgarie
  • Importance paléogéomorphologique et paléogéographique des altérites à saprolites pour l'étude de la formation du relief des montagnes dans le sud de la Bulgarie
  • Altérite ; Bulgarie ; Datation ; Formation superficielle ; Montagne ; Roche ; Saprolite ; Sédimentologie
  • Résultats des observations effectuées de 1986 à 1990. Etude de la structure et de la répartition des altérites à saprolites. Les saprolites sont fréquentes à différents niveaux d'interfluves et dans les vallées fluviales; leur distribution ne montre
  • aucune relation avec les surfaces d'érosion. Dans de nombreux sites les affleurements de saprolites ont une épaisseur de 3 à 8 m et plus. Les résultats de l'analyse lithologique et minéralogique sont donnés, ainsi que la description complète de 2 secteurs
  • à saprolites dans les monts Vitoša et Plana. On a essayé de dater les saprolites du Miocène-Quaternaire.
Long-term isovolumetric leaching of aluminium from rocks during weathering : implications for the genesis of saprolite
  • Long-term isovolumetric leaching of aluminium from rocks during weathering : implications for the genesis of saprolite
  • 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
Relief and saprolites through time on the Baltic Shield
  • Relief and saprolites through time on the Baltic Shield
  • The analysis of the relationship between relief, saprolite, and cover rocks through time led to the conclusion that the most important factor for the present relief differentiation is the time of exposure of the basement surface during
Characteristics and significance of two pre-late-Wisconsinan weathering profiles (Adirondacks, USA and Miramichi Highlands, Canada)
  • The purpose of this paper is to stress the importance of saprolite characterization for consideration on climatic conditions during saprolite formation and age of saprolites. Two weathering profiles located north of the Quaternary glacial limit have
In situ weathered rocks on plateaus, slopes and strandflat areas of the Lofoten-Vesteralen, North Norway
  • Géographie de l'Europe ; Géomorphogenèse ; Lofoten-Vesteralen ; Météorisation ; Norvège ; Saprolite
  • Thick sandy-silty saprolites occur on some plateaus and lower areas of the Lofoten-Vesteralen islands. Their location and their thickness (up to 8 m) suggest a pre-Weichselian or pre-glacial origin. But their composition does not imply warmer
  • climatic conditions than now. Thus an influence of post-glacial weathering cannot be excluded, though these saprolites are probably significant for the knowledge of the pre-glacial landscape development.
A plan for a geochemical study on weathered bedrock in Northern Finland
  • Finlande ; Formation superficielle ; Géochimie ; Géographie de l'Europe ; Météorisation ; Projet de recherche ; Saprolite
Characteristics and significance of pre-Wisconsinan saprolites in the northern Appalachians in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • Characteristics and significance of pre-Wisconsinan saprolites in the northern Appalachians in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • puis la précipitation du fer, et aussi de faibles pertes en bases. Le minéral argileux principal des saprolites est la kaolinite. L'étude du Be 10 dans les tills et les saprolites donne des âges minimum de plus de 100 000 ans dans 2 profils. Discussion
The critical role of climate and saprolite weathering in landscape evolution
  • The critical role of climate and saprolite weathering in landscape evolution
  • Here, the AA. report rates of erosion and weathering in saprolite and soil to quantify how climate influences denudation, by focusing on an elevation transect in the western Sierra Nevada Mountains, California. They use an adapted mass balance
  • approach and couple soil-production rates from the cosmogenic radionuclide (CRN) 10Be with zirconium concentrations in rock, saprolite and soil. The results quantify links between climate, weathering and erosion, and together suggest that climate controls
  • chemical weathering via temperature and moisture control on chemical reaction rates. They also suggest that saprolite weathering reduces bedrock coherence, leading to faster rates of soil transport that, in turn, decrease material residence times
Smectite formation produced by weathering in a coarse granite saprolite in Galicia (NW Spain)
  • Smectite formation produced by weathering in a coarse granite saprolite in Galicia (NW Spain)
Interactions between perched and saprolite aquifers on a small, salt-affected and deeply weathered hillslope
  • Interactions between perched and saprolite aquifers on a small, salt-affected and deeply weathered hillslope
Modification of old land surfaces by ice sheets in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • Modification of old land surfaces by ice sheets in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
La question des altérites profondes dans la région des Hébrides internes (Ecosse occidentale) in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.
  • La question des altérites profondes dans la région des Hébrides internes (Ecosse occidentale) in Weathered mantles (saprolites) over basement rocks of High Latitudes = Les manteaux d'altération sur les socles des Hautes Latitudes.