problems and concepts of paleopedology in Argentina

MARCELO ZÁRATE; PERLA IMBELLONE

QUATERNARY INTERNATIONAL

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: amsterdam; Año: 1998 vol. 5152 p. 28 - 30

1040-6182

Pedogenesis has played a major role in the evolution of the Pampean landscape which resulted in the common occurrence of pedogenic features in the stratigraphic successions, but has not been recognized in previous studies. The main problems facing paleopedological research are the identification of paleosol profiles, paleosol horizons and their interpretation. Paleosols have been traditionally interpreted as truncated profiles because A and E horizons were not recognized. This may be apparent or real. Erosion generally leaves supporting evidence such as a lag deposit, but superposed cycles of pedogenesis can obliterate original morphological properties, which alters the appearance of buried A and E horizons. Abrupt boundaries have always been interpreted as erosional surfaces because of an overgeneralization that all land surfaces are eroded. When paleosols are exposed in roadcuts and quarries, they acquire new morphological features such as induration and tension cracks, which have been misinterpreted as original properties. In the current view, the basic criteria for paleosol recognition in exposures are based on the vertical and lateral arrangements of soil morphological features within a detailed stratigraphic framework provided by sedimentary facies analysis. The framework can be verified by micromorphological studies of polygenetic horizons to determine the sequence of episodes of pedogenesis and to evaluate the effects of diagenesis following burial.