Influence of diagenetic processes and terrestrial/anthropogenic sources in the REE contents of the Cascais submarine canyon (Iberian western coast)

Temporal variations of rare earth elements (REE) and their fractionation patterns, major elements, Pb Hg were determined in two multicores collected at 445 2100 m water depth (mwd) the Cascais submarine canyon (CSC). The PAAS-normalized REE patterns suggest mixing Tagus estuarine marine sediments, marked by MREE (Nd?Dy series) enrichment positive Eu-anomaly, with sediments. Eu/Eu* implies incorporation detrital feldspar minerals derived from estuary. Ce/Ce*, (La/Yb) PAAS (Nd/Yb) show differences between cores. Core 252-35 shallower site is enriched HREE (Ho?Lu over LREE (La?Pr series), a pattern also found estuary vicinity an abandoned chemical complex, where environment affected legacy massive-sulfide ores processing. There seems to be only limited down-canyon sediment transport deeper reaches core 252-32 was collected. This shows Ce/Ce* peaks coinciding low values suggesting preferential diagenetic remobilization relative HREE. Upcore Pb/Al Hg/C org trends observed both cores indicate dispersion anthropogenic component through CSC, which less obvious ?REE/Al particularly site. may influence processes signal, associated relatively accumulation rates. • contents measured input contaminated CSC Influence reflected signal signature contamination clearer than that REE. cannot considered as contaminants emerging concern