Sedimentological analysis of sandy - gravel accumulations, Serra da Estrela plateaux (Portugal)

• Autorzy: Vieira G.T. , Mycielska-Dowgiałło E. , Woronko B.
• Języki publikacji: EN

Abstrakty

EN

Sandy-gravel accumulations are frequent features on the plateaux of the Serra da Estrela II and other granitic mountains in Portugal. Their genesis has been attributed to both eolian and water processes and a detailed sedimentological study is needed to better understand the mechanisms involved. The present paper provides results obtained from the heavy mineral analysis and optical and scanning electron microscope study of samples from two sandy-gravel accumulations from the Serra da Estrela. The results indicate that the finer fractions of the original sediment have been illuviated. A well-sorted surface layer and poorly sorted subsurface of the accumulation have resulted from this process. A very short duration of eolian processes is evident from the analysis. Although wind seems to have been the responsible for the morphology of the accumulation, its action was not enough to produce significant abrasion in the surface of quartz grains.

Słowa kluczowe

EN

wind erosion; water erosion; scanning electron microscopy; Central Cordillera; Portugal

• Wydawca: Stowarzyszenie Geomorfologów Polskich
• Czasopismo: Landform Analysis
• Rocznik: 2003
• Tom: Vol. 4
• Strony: 99--107
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Vieira G.T.

• University of Lisbon Centro de Estudos Geográficos Faculdade de Letras Alameda da Universidade 1600-214 Lisboa, Portugal

autor

Mycielska-Dowgiałło E.

• University of Warsaw Faculty of Geography and Regional Studies Krakowskie Przedmieście 30 00-927 Warszawa, Poland

autor

Woronko B.

• University of Warsaw Faculty of Geography and Regional Studies Krakowskie Przedmieście 30 00-927 Warszawa, Poland

Bibliografia

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