FORMATION OF FE-MN NODULES IN THE GUATEMA LAN BASIN - RARE-EARTH ELEMENT EVIDENCE

The behavior of rare-earth elements (REE) and their labile fraction in seafloor nodules and sediments from 12 stations located in the Guatem alan Basin, Pacific Ocean, are examined. REE were sorbed by Fe oxyhydr oxides of hydrothermal origin. As a result of subsequent diagenesis, t hese were transformed into nodules and retained their primary REE patt ern. The chemical composition of nodules and sediments gradually chang es from south to north in the study area owing to increasing distance from the thermal source in the Galapagos spreading center. This sugges ts that the rates of accretion of the nodules and sedimentation are si milar.