Genesis of some selected soils in the Valdés Peninsula, NE Patagonia, Argentina.

BOUZA, P.; MARIANO SIMÓN,; JOSÉ AGUILAR,; MARIO ROSTAGNO,; HÉCTOR DEL VALLE,

Sustainable Use and Management of Soils in Arid and Semiarid Regions- Advances in Geo Ecology

CATENA VERLAG GMBH

Lugar: Reiskirchen; Año: 2005; p. 1 - 12

Four soil profiles from two region in the Valdés Penísula (NE Patagonia, Argentina) were studied. The detailed field and laboratory studies indicated that these soils were formed from three different successive erosional-depositional episodes alternating with pedogenic episodes and seven successive stage of soil formation. During the first pedogenic episode, the primary soil forming processes were leaching of carbonates and clay iluviation from which only the remains of the calcic horizon and the transformation of smectite to palygorskite were preserved. This was followed by an erosion process, and from the second pedogenic episode the calcic and argillic horizons were preserved. Clay coatings were partially disturbed and illite was transformed to smectite. Between 19,000 and 15,000 yrs the clay iluviation was promoted by the presence of high Na+ content in the exchangeable site, forming a nitric horizon. Finally, an aeolian  sand deposit covered these soils and at the present the soil materials are redistributed by the wind, accentuating the current mound-intermound morphology