REE distribution patterns plotted for the nine representative samples plot in a restricted field (Fig. 1) (sample numbers are the same as the core number). Results for all of the REE analyses are available for these samples, except for samples 16 and 17, where Tb is <0.5 ppm (which is apparently below the detection limit). For some of the samples, one or more REE are reported as below the detection limit (not plotted in Fig. 1), including Eu (detection limit = 0.2 ppm). This means, in effect, that a negative Eu anomaly exists, although this is not readily apparent in Figure 1. Disregarding this aspect of the REE distribution, the pattern for the representative samples is contained within a field only slightly more compressed than that enclosing all 48 samples (dashed lines). Except for their close similarity, these patterns exhibit no systematic relative order in quantitative terms. Thus, the pattern for one of the deepest samples, sample 48 (at 424.89 mbsf), plots at the top of Figure 1 directly adjacent to sample 3 (at 17.40 mbsf). The inset at top left of this diagram shows the total concentrations of REE in Atlantic and Pacific seawater, normalized to NASC (after Liu et al., 1988).
The average ratio of normalized La/Lu is 0.86 in these samples, thus quantifying a slight enhancement in HREE over LREE, a feature also evident in Figure 1. A distinct negative Ce anomaly is present in all samples and is here quantified using one of several algorithms, Cean= Cen/Ce*, where Ce* is the value expected for Ce3+, interpolating neighboring trivalent REE (La-Nd). For Site 1014 samples, Cean ranges from 0.49 to 0.81.
Shale-normalized Eu/Sm ratios range from 0.19 to 0.46, averaging 0.26. The concentration of uranium ranges from 4.3 to 25 ppm, and U/Th ratios range from 1.45 to 5.68, averaging 2.64.
The extent of covariance among 16 selected samples (see Table 1) of the sum of the eight analyzed REE and CaCO3 through Subunits IA and IB, is shown in Figure 2. Plots of La/Lu and Ce* vs. depth in Hole 1014A are shown in Figure 3.