Chondrite-normalized REE patterns

A few REE data on hydrothermal solutions are available (Fig. 2.34). Chondrite normalized REE patterns of hydrothermal solutions from Vienna Wood, Pacmanus and Desmos, Manus Basin exhibit positive Eu anomaly and LREE enrichment are similar to midoceanic ridge solution and Kuroko ore fluids. This positive Eu anomaly (Fig. 2.35) may have been caused by the selective leaking of Eu due to the interaction of an ascending hydrothermal solution and footwall volcanic rocks (Gena et al., 2001). It is interesting to note that altered basaltic andesite has a negative Eu anomaly and this feature is the same as that found in the Kuroko mine area (Shikazono, 1999). 

Chondrite-normalized REE patterns were based on values by Evensen et al. (1978) averaging the samples firstly determined in ppm for each site. 

Chondrite-normalized REE patterns show that all types of dykes are depleted in HREE relative to LREE (Fig. 5). Also dykes display high SrA (ave. 86 ppm) and La/ Yb (up to 80 ppm) ratios. 

Fig. 5. Cl chondrite-normalized REE patterns showing the low HREE relative to LREE, suggesting a garnet-bearing and plagioclase-free source, as well as an adakitic-geochemical composition.

Selandian Rb-Sr ages of 59.6 2.8 Ma and 60.3 0.8 Ma were determined for the K1A and K19 bodies, respectively these bodies occur in the southwestern part of the field and are either barren of diamond or have the poorest diamond results within this field (Hood McCandless 2004 Fig 1). Mineralogical (e.g., amphibole, sanidine) and geochemical evidence (e.g., flatter chondrite-normalized REE pattern versus the steep profile of typical kimberlite) enticed Eccles et al. (2008) to conclude that these rocks are better referred to as hybrid kimberlite-ultrabasic rocks. 

The chondrite-normalized REE patterns for basement-hosted uranium oxides are similar, except for a small variation of LREE abundances, indicating identical physico-chemical deposition conditions (T, pH, fluid composition) for the Eastern part of the Athabasca Basin basement. The previous REE distinction made between Ingress and Egress deposits (Fayek Kyser 1997) is not confirmed by the present study, because both types have similar REE abundance and fractionations, indicating the similarity of the sources and the processes for both deposit types. Thus, these results suggest... 

Figure 5. Chondrite-normalized REE patterns for some soapstone outcrops along the eastern U,S. Piedmont. The source is indicated by the abbreviation of the state. The Md. sample is from Ednor quarry, Montgomery County, MD Va. is from the Albemarle-Nelson County, VA quarry Pa. (A) and (B) are representative of the two types of samples from outcrops in Lancaster and Chester Counties, PA N.C. is from an outcrop in Watuga County, NC R.L is from Oaklawn, RI and Mass, is from Westfield, Mass.

Figure 12. Chondrite-normalized REE patterns from quarries and artifacts in Labrador and Newfoundland. Sample N is from the Fleur-de-Lys quarry on the east coast of Newfoundland L from an outcrop near the Viking habitation site at Vanse aux Meadows in northern Newfoundland F from soapstone outcrops in the Freestone Harbor region and M from outcrops of Moore s and Okak Islands on the central Labrador coast. Both E and A are artifacts which represent a group of artifacts having similar REE patterns but for which no quarry of origin has been found.

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. 

Chondrite-normalized REE patterns. With regard to chondrite-normalized REE distributions in whole rocks, the tectonically emplaced and abyssal peridotites may be subdivided in six main groups ... 

Figure 15 Illustration of the effects of host-rock contamination on whole-rock REE geochemistry. Chondrite-normalized REE patterns of measured whole-rock peridotites compared with REE abundances calculated from modal data plus mineral compositions. Also compared are mixtures of calculated whole-rock and kimberlite for each diagram. Two specimens, (a) and (b) are high-r and low-T garnet Iherzolites from Somerset Island, Nunuvut (Canada) (after Schmidberger and Erancis, 2001).

Figure 17 Summary fields of chondrite-normalized REE patterns for whole-rock peridotites and cUnopyroxenes for peridotite xenoliths. Noncratonic whole-rock peridotites are either LREE-depleted (type lA least common) or LREE-enriched (type IB most common). Data sources from Stosch and Seek (1980), Stosch and Lugmair (1986), Menzies et al (1985). Clinopyroxenes from these rocks also show LREE enrichment or depletion. Cratonic peridotite whole rocks are ubiquitously LREE-enriched. Low-T (granular) suite show greater LREE/HREE compared to high-T (sheared) suite and this is reflected in the more LREE-enriched clinopyroxene compositions in the low-T suite. Data sources from Shimizu (1975), Nixon et al. (1981), and Irvine (2002). Low-T whole-rock suite includes 19 samples...

Figure 4 Comparison between the Archean upper crust (UC) and the contemporary upper crust of Rudnick and Gao (see Chapter 3.01) (R G) with respect to chondrite-normalized REE patterns (normalizing values from Anders and Grevesse, 1989). Archean data are from Condie (1993) and Taylor and McLennan (1995) (T M 1995).

Figure 3. Chondrite-normalized REE patterns showing the range of patterns found for soapstone from the Fleur de Lys quarry in Newfoundland. Curves 1 (o) and 2 (x) represent range of concentrations for most of the samples curve 3 (%) is the somewhat different pattern that was more typical of the Locality 2 soapstone. Range of REE patterns typical of the soapstone outcrops at Peabody Point is shown by curves 4 (n) and 5 (m).

Figure 4. Chondrite-normalized REE patterns for representative soapstone samples from outcrops in the Okak area. Curves 1 (O) and 2 (%) are the types of patterns found at the Cojfin Island outcrop curve 3 (x) is an outcrop at Moores Island curve 4 (Aj is typical of the Nutak outcrop.

Figure 4. The three chondrite-normalized REE patterns characteristic of Yagi soil profiles pattern 1 (%), pattern 2 (M), and pattern 3 (O). Pattern 2 is subdivided into 2a and 2b. That shown here is for 2a. Pattern 2b has a similar shape but has lower values.

Figure 5. Chondrite-normalized REE patterns for the N124, EDO profile showing the change in pattern with depth. The figure has been divided into two sections for clarity. Key pattern 1 pattern 2 O, pattern 3.

The chemical diversity of mantle pyroxenites is also patent from REE variations. Figure 26 shows the chondrite-normalized REE patterns of representative pyroxenites from orogenic peridotite massifs in Eastern Pyrenees (Lherz and Freychi-nede) and the Betico-Rifean Belt (Ronda and Beni Bousera). These rocks show variable REE distributions, but some relationships are observed between the structural and/or mineralogical types of pyroxenites and the REE patterns ... 

Fig. 10. Chondrite-normalized REE patterns of (A) siderite, ankerite and (B,C) calcite in the Oseberg Formation. The numbers in the key boxes refer to the analysis numbers in Table 4. In (C) a same symbol shape denotes different samples coming from a single calcite-cemented layer in a same well.

Figure 17. Chondrite-normalized REE patterns for coeval portions of 100 and 001 sectors of a single fluorapatite crystal from the Siglo XX Mine, Llallagna, Bolivia. Sectoral difference in the concentration of La is almost an order of magnitude. [Modified after Rakovan et al. (1997).]...

Chondrite-normalized REE patterns calculated for olivine fractionation from a komadite melt komatiite-336) at 30%, 50%, 70% and 90% fracdonal crystalli2ation. The partition coefficients were taken from Table 4.1. The details of the calculations made for each of the ten REE shown using Eqn [4.18] are given in Table 4.15. 

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...

Figure 4 Chondrite-normalized REE patterns for selected REE ores from Bayan Obo and Mountain Pass ion absorption clay ores from Longnan and Ximwu, China and heavy mineral placer concentrates (monazite from Queensland Australia and xenotime from Malaysia) . Note that the ion absorption clay REE patterns are normalized to 100%.

Figure 5 Chondrite-normalized REE patterns for selected cal-cium-alumimmi inclusions (CAI) from the Allende carbonaceous chondrite and refractory mineral grains (perovskite, hibonite) from the Murchison carbonaceous chondrite." The highly irregular REE patterns, including anomalies for the least refractory Ce, Eu, and Yb, are indicative of localized very high temperatures leading to complex REE evaporation/condensation processes...

Figure 6 Chondrite-normalized REE patterns of the primitive mantles and crusts of Earth, Mars, and the Moon. For the Earth, the continental crust is shown for the Moon, the highland crust is shown and for Mars, the bulk crust is shown...

Figure 7 Chondrite-normalized REE patterns of selected rocks and reservoirs from oceanic crustal environments. Note that MORE and DMM have parallel REE patterns, a reflection that MORE is derived from DMM by high degrees (>10%) of partial melting. Also note that pelagic clays have REE patterns similar to shales derived from the upper continental crust. The slight negative Ce anomaly is significant and reflects a small component of authigenic material derived from seawater...

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