L. Minarik et al., THE BEHAVIOR OF RARE-EARTH ELEMENTS AND Y DURING THE ROCK WEATHERING AND SOIL FORMATION IN THE RICANY GRANITE MASSIF, CENTRAL BOHEMIA, Science of the total environment, 215(1-2), 1998, pp. 101-111
The geochemistry of rare-earth elements (REE) and yttrium has been stu
died in the soil profile derived from a biotite granite in the area of
'Forest Brook Catchment' (FBC) near Ricany (Central Bohemia, the Czec
h Republic). The comparison of the variation in the REE and Y concentr
ations in the individual zones of the profile shows that total content
of lanthanides depends on the grain size of the soil material. The ho
rizons abundant in clay fraction (Gr(1), Gr(2)) contain five times mor
e REEs than those with a predominance of silt and sand (G(0), Gr(3)).
The chondrite-normalised soil La-Lu pattern is similar in all profile
zones and it behaves as an almost smooth function of the REE ionic rad
ii, or their atomic numbers, respectively. The bulk content of lanthan
ides in soil is higher than that in the local partly weathered boulder
s of the parent rocks (syeno- and monzogranite). The content of acid s
oluble forms of REE (the portion of elements soluble in 0.1 M HNO3) in
creases from the umbric horizon A towards the bottom of the profile. O
ur results indicate that the mobile part of REE is leached and transpo
rted to the lower part of the profile by acidic atmospheric precipitat
ion. The REE distribution pattern of surface-and subsurface waters dra
ining the terrain of the catchment confirms this consideration. (C) 19
98 Elsevier Science B.V.