Soils Developed from Different Volcanic Rocks from the Fernando de Noronha Island: Rare-Earth Element Patterns and Isotopic Lead Composition

Abstract

This study examines the infl uence of pedogenesis on the distribution of rare earth elements in soils derived fromdifferent rock types and formed under tropical humid climate, as well as the possible contribution of airborne Pb to thesesoils. We studied 5 soil profi les developed from different volcanic rocks cropping out in the Fernando de Noronha island.Results show that in the course of weathering, the soils were enriched in REE. The REE patterns of the soils are similarto those of the parent material, except for a slight HREE enrichment. Lead-isotope data indicate the presence of a nonradiogenicanthropogenic component in the upper horizons of the soil profi les.

Keywords

• Soils
• Fernando de Noronha island
• Geochemistry
• REE
• Pb isotopes