Trace Element Geochemistry of North Atlantic Aeolian Dusts

Abstract

WIND-TRANSPORTED (aeolian) dusts make a significant contribution to the land-derived material of some deep-sea sediments^1–4 and this is particularly significant in the region of the North Atlantic between about 10° N and about 35° N. This region underlies the path of the north-east trade winds which have crossed the Sahara Desert area, and which contain one of the highest reported dust-loadings found in the marine atmosphere⁵. These dusts are important in introducing trace elements into the oceans in association with solid material. Few analyses^3,6 are available of the trace element content of aeolian dusts, however, none of which give an overall estimate of the trace element content of dusts in the north-east trade winds of the North Atlantic. This report presents the preliminary results of a study of the trace element composition of dusts collected from the north-east trades, the north-east trades-westerlies boundary region and the westerlies in the western North Atlantic in the area between about 17° N and about 55° N. As well as a series of trace elements, analyses are also given for the geochemically important elements iron and manganese.