Chondrite normalization trace elements

REE (Eigure 10), thorium and zirconium (Figure 11). Conventional, chondrite-normalized REE patterns are shown in Eigures 12-15 for whole rocks and in Eigures 18 and 22 for cpx. Primitive mantle-normalized trace-element patterns are shown in Eigures 16 and 17 for whole rocks and Eigure 21 for minerals. 

Figure 17 (a) Chondrite-normalized rare earth element patterns and (b) primitive-mantle normalized trace element... 

Figure 24 Concentration profiles of siderophile elements in a radially zoned Fe,Ni grain in the CBb chondrite, QUE 94411 (a) electron microprobe data (b) and (c) trace element data from laser ablation ICPMS (Campbell et ai, 2001). The nickel, cobalt, and chromium profiles can be matched by nonequilibrium nebular condensation assuming an enhanced dust-gas ratio of —36 X solar, partial condensation of chromium into silicates, and isolation of 4% of condensates per degree of cooling (Petaev etal, 2001). Concentrations of the refractory siderophile elements, osmium, iridium, platinum, ruthenium, and rhodium, are enriched at the center of the grain by factors of 2.5-3 relative to edge concentrations, which are near Cl levels after normalization to iron (reproduced by permission of University of Arizona on behalf of The Meteoritical Society from Meteorit. Planet. ScL, 2002, 37, pp. 1451-1490).

Figure 17 Comparison of (a) rare-earth and (b) additional trace-element compositions of the upper, middle, and lower crust recommended here. Chondrite values from Taylor and McLennan (1985), mantle-normalizing values...

Figure 3 Chondrite-normalized REE patterns for common igneous rock-forming minerals. The igneous rock type from which the mineral was extracted is also listed. Data from compilation provided by T ay lor and McLennan. The extreme range of REE and the distinctive patterns for certain minerals is one of the reasons why REE are valuable trace elements for evaluating petrogenesis...

Aubrites are depleted in siderophile elements relative to chondritic abundances. Excluding Shallowater, bulk rocks have Cl-normalized Fe/Si ratios of 0.006-0.055. Shallowater, with a higher modal metal content (3.7% versus <0.7% Watters and Prinz, 1979), has a Cl-normalized Fe/Si of 0.33 (Easton, 1985). Trace siderophile elements are also depleted for example, excluding dark samples, iridium varies from —10 X Cl to 10 X Cl. Dark clasts from Khor... 

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