Figure F76. Downhole variation of the abundance of the trace element yttrium over the entire depth of Hole 735B (Legs 118 and 176) based on 357 whole-rock analyses (see text for sources). The yttrium data have been recast as logarithmic chondrite-normalized values for ready comparison with the normalized abundances of heavy REE, for which yttrium is a proxy. The clinopyroxene-poor troctolites from Leg 118 Units III and VI are depleted in yttrium and, by inference, heavy REE and other incompatible trace elements. However, these elements are highly enriched in the felsic veins and many oxide-rich gabbros. Symbols are as in Figure F64.