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Three pyroclastic deposits from Monte Yulture volcanic area (Potenza, southern Italy) looking like paleosols in the field were investigated in a previous study for mineralogy and major elements to estimate the stage of the weathering. Here is dealt with the behaviour of sorne trace elements (Ce, La, Ba, Ni, Cr, Y, Rb, Sr, Y, Zr and Nb) in the same deposits to give a comprehensive geochemical picture.  The distribution of the chemical elements within the whole rock and after its attack with Na-pyrosulfate (residue + solute) has been considered. Ba and Sr, as well as their distribution, appear to be controlled by the residual crystals in each of the deposits; La, Ce, Y and Nb are more concentrated in the solute that once was represented by vitric component, allophane, and Fe-Si-Al gels, biotite, carbonates and analcite; Y, Cr, and Ni show similar trends in whole rock and in solute. In particular La, Ce, Y, Y, Cr and Ni in the lowermost unit increase with the depth, as well as the contents of gels and allophane. Probably this behaviour was superimposed by the fluctuation of the water tables, as documented by the occurrence of a carbonate level upon the unit lies. It is concluded that the earliest stage of weathering did not affect the trace element distribution and that interpretations about chemical changes in deeply altered pyroclastic rocks should be always the outcome of careful accurate analyses.  En un trabajo previo se estudiaron tres dep&#243;sitos pirocl&#225;sticos, considerados como paleosuelos, del &#225;rea volc&#225;nica del Monte Yulture (Potenza, Italia) para deducir su grado de meteorizaci&#243;n. En el presente trabajo se estudia el comportamiento de algunos elementos traza (Ce, La, Ba, Ni, Cr, Y, Rb, Sr, Y, Zr, Nb) en esos dep&#243;sitos para intentar obtener una imagen geoqu&#237;mica m&#225;s completa.  Se ha estudiado la distribuci&#243;n de elementos traza en la roca total y despu&#233;s de un ataque con pirosulfato-Na (residuo + soluci&#243;n). Ba y Sr parecen estar controlados por los cristales del residuo (piroxenos, feldespatos, anf&#237;boles y accesorios); La, Ce, Y y Nb se concentran m&#225;s en la soluci&#243;n, es decir en los componentes v&#237;treos, alofana, geles Fe-SiAl, biotita carbonatos y analcima; Y, Cr y Ni no muestran ninguna tendencia a concentrarse en una fracci&#243;n concreta. Hay que resaltar que La, Ce, Y, Y, Cr y Ni aumentan con la profundidad en la unidad inferior, junto con el contenido en geles y en alofana. Este comportamiento puede ser debido a fluctuaciones del nivel fre&#225;tico, como se deduce por la presencia de un nivel calc&#225;reo en la unidad superior.  Se concluye que los estados precoces de meteorizaci&#243;n no afectan pr&#225;cticamente a la distribuci&#243;n de los elementos traza, y que las interpretaciones sobre los cambios qu&#237;mico sufridos por las rocas pirocl&#225;sticas deben hacerse s&#243;lo despu&#233;s de un detallado an&#225;lisis

Distribution of trace elements in altered pyroclastites from Monte Vulture volcano (southern Italy)