Journal
GEODERMA
Volume 138, Issue 1-2, Pages 39-48Publisher
ELSEVIER
DOI: 10.1016/j.geoderma.2006.10.008
Keywords
oxisols; polygenesis; soil mineralogy; soil micromorphology; soil formation
Categories
Ask authors/readers for more resources
In geologically stable areas in the tropics, climatic changes and geomorphic cycles give origin to polygenetic soils. Polygenesis involves new soil formation phases taking place on preweathered materials from previous phases, resulting in soils with rather similar chemical and mineralogical properties. Polygenetic soils from Minas Gerais, Brazil, were investigated with the purpose of distinguishing mineralogical aspects in relation to polygenesis. The soil materials were studied by micromorphology and electron microscope and analyzed by XRD. All soils are strongly weathered and even show weathered grains of ilmenite and quartz. The soils show two phases of kaolinite formation (pseudomorphs after mica and precipitation from solution) and of accumulation of iron compounds. Desilication causes gibbsite formation from kaolinite, occasionally even in the deep saprolite. Superposed processes can be due to progressively deeper weathering or to changes of the external environment. (c) 2006 Elsevier B.V All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available