Clay-sized minerals in permafrost-affected soils (Cryosols) from King George Island, Antarctica
Simas, Felipe N. B. (UNEC - Centro Universitário de Caratinga. Mestrado em Meio Ambiente e Sustentabilidade)
Schaefer, Carlos Ernesto G. R. (Universidade Federal de Viçosa. Departamento de Solos)
Melo, Vander F. (Universidade Federal do Paraná. Departamento de Solos e Engenharia Agrícola)
Guerra, Marcelo B. B. (Universidade Federal de Viçosa. Departamento de Solos)
Saunders, Martin (The University of Western Australia. Centre for Microscopy and Microanalysis)
Gilkes, Robert J. (The University of Western Australia. School of Earth and Geographical Sciences)

Data:	2006
Resum:	Cryosols from Maritime Antarctica have been less studied than soils from continental areas of Antarctica. In this work X-ray diffraction, difference X-ray diffraction, differential thermal analysis, thermogravimetry, transmission electron microscopy/energy dispersive spectroscopy and selective chemical dissolution were used to characterize the clay fraction of basaltic, acid sulfate and ornithogenic Cryosols from ice-free areas of Admiralty Bay, King George Island. Non-crystalline phases are important soil components and reach >75% of the clay fraction for some ornithogenic soils. Randomly interstratified smectite-hydroxy-Al-interlayered smectite is the main clay mineral of basaltic soils. Kaolinite, chlorite and regularly interstratified illite-smectite predominate in acid sulfate soils. Jarosite is also an important component of the clay fraction in these soils. Crystalline Al and Fe phosphates occur in the clay at sites directly affected by penguin activity and the chemical characteristics of these ornithogenic sites are controlled by highly reactive, non-crystalline Al, Si, Fe and P phases. Chemical weathering is an active process in Cryosols in Maritime Antarctica and is enhanced by the presence of sulfides for some parent materials, and faunal activity.
Drets:	Tots els drets reservats.
Llengua:	Anglès
Document:	Article ; recerca ; Versió publicada
Matèria:	Allophane ; Clay Minerals ; Cryosols ; Maritime Antarctica ; Ornithogenesis ; Phosphate ; Soils ; X-ray Amorphous Phases
Publicat a:	Clays and Clay Minerals, Vol. 54, Núm. 6 (2006) , p. 721-736, ISSN 1552-8367

DOI: 10.1346/CCMN.2006.0540607

16 p, 1.7 MB  Accés restringit a la UAB

El registre apareix a les col·leccions:
Articles > Articles de recerca
Articles > Articles publicats